What do proper fractions look like? Equal and unequal fractions, comparison of fractions

We come across fractions in life much earlier than we begin studying them at school. If we cut a whole apple in half, we get ½ of the fruit. Let's cut it again - it will be ¼. These are fractions. And everything seemed simple. For an adult. For a child (and this topic begins to be studied at the end of primary school), abstract mathematical concepts are still frighteningly incomprehensible, and the teacher must clearly explain what a proper and improper fraction, common and decimal are, what operations can be performed with them and, most importantly, why all this is needed.

What are fractions?

Introducing a new topic at school begins with ordinary fractions. They are easily recognized by the horizontal line separating the two numbers - above and below. The top one is called the numerator, the bottom one is the denominator. There is also a lowercase option for writing improper and proper ordinary fractions - through a slash, for example: ½, 4/9, 384/183. This option is used when the line height is limited and it is not possible to use a “two-story” entry form. Why? Yes, because it is more convenient. We'll see this a little later.

In addition to ordinary fractions, there are also decimal fractions. It is very simple to distinguish them: if in one case a horizontal or slash is used, in the other a comma is used to separate sequences of numbers. Let's look at an example: 2.9; 163.34; 1.953. We intentionally used a semicolon as a separator to delimit the numbers. The first of them will read like this: “two point nine.”

New concepts

Let's return to ordinary fractions. They come in two types.

The definition of a proper fraction is as follows: it is a fraction whose numerator is less than its denominator. Why is it important? We'll see now!

You have several apples, halved. Total - 5 parts. How would you say: do you have “two and a half” or “five and a half” apples? Of course, the first option sounds more natural, and we will use it when talking with friends. But if we need to calculate how many fruits each person will get, if there are five people in the company, we will write down the number 5/2 and divide it by 5 - from a mathematical point of view, this will be more clear.

So, for naming proper and improper fractions, the rule is this: if a whole part can be distinguished in a fraction (14/5, 2/1, 173/16, 3/3), then it is irregular. If this cannot be done, as in the case of ½, 13/16, 9/10, it will be correct.

The main property of a fraction

If the numerator and denominator of a fraction are simultaneously multiplied or divided by the same number, its value does not change. Imagine: they cut the cake into 4 equal parts and gave you one. They cut the same cake into eight pieces and gave you two. Does it really matter? After all, ¼ and 2/8 are the same thing!

Reduction

Authors of problems and examples in mathematics textbooks often seek to confuse students by offering fractions that are cumbersome to write but can actually be abbreviated. Here is an example of a proper fraction: 167/334, which, it would seem, looks very “scary”. But we can actually write it as ½. The number 334 is divisible by 167 without a remainder - after performing this operation, we get 2.

Mixed numbers

An improper fraction can be represented as a mixed number. This is when the whole part is brought forward and written at the level of the horizontal line. In fact, the expression takes the form of a sum: 11/2 = 5 + ½; 13/6 = 2 + 1/6 and so on.

To take out the whole part, you need to divide the numerator by the denominator. Write the remainder of the division on top, above the line, and the whole part - before the expression. Thus, we get two structural parts: whole units + proper fraction.

You can also carry out the inverse operation - to do this, you need to multiply the integer part by the denominator and add the resulting value to the numerator. Nothing complicated.

Multiplication and division

Oddly enough, multiplying fractions is easier than adding. All that is required is to extend the horizontal line: (2/3) * (3/5) = 2*3 / 3*5 = 2/5.

With division, everything is also simple: you need to multiply the fractions crosswise: (7/8) / (14/15) = 7*15 / 8*14 = 15/16.

Adding Fractions

What to do if you need to perform addition or they have different numbers in the denominator? It will not work to do the same as with multiplication - here you should understand the definition of a proper fraction and its essence. It is necessary to bring the terms to a common denominator, that is, the bottom of both fractions should have the same numbers.

To do this, you should use the basic property of a fraction: multiply both parts by the same number. For example, 2/5 + 1/10 = (2*2)/(5*2) + 1/10 = 5/10 = ½.

How to choose which denominator to reduce the terms to? This must be the minimum number that is a multiple of both numbers in the denominators of the fractions: for 1/3 and 1/9 it will be 9; for ½ and 1/7 - 14, because there is no smaller value divisible by 2 and 7 without a remainder.

Usage

What are improper fractions used for? After all, it is much more convenient to immediately select the whole part, get a mixed number - and be done with it! It turns out that if you need to multiply or divide two fractions, it is more profitable to use irregular ones.

Let's take the following example: (2 + 3/17) / (37 / 68).

It would seem that there is nothing to cut at all. But what if we write the addition result in the first parentheses as an improper fraction? Look: (37/17) / (37/68)

Now everything falls into place! Let's write the example in such a way that everything becomes obvious: (37*68) / (17*37).

Let's cancel 37 in the numerator and denominator and finally divide the top and bottom by 17. Do you remember the basic rule for proper and improper fractions? We can multiply and divide them by any number as long as we do it for the numerator and denominator at the same time.

So, we get the answer: 4. The example looked complicated, but the answer contains only one number. This happens often in mathematics. The main thing is not to be afraid and follow simple rules.

Common Mistakes

When implementing, a student can easily make one of the common mistakes. Usually they occur due to inattention, and sometimes due to the fact that the material studied has not yet been properly stored in the head.

Often the sum of numbers in the numerator makes you want to reduce its individual components. Let’s say in the example: (13 + 2) / 13, written without parentheses (with a horizontal line), many students, due to inexperience, cross out 13 above and below. But this should not be done under any circumstances, because this is a gross mistake! If instead of addition there was a multiplication sign, we would get the number 2 in the answer. But when performing addition, no operations with one of the terms are allowed, only with the entire sum.

Guys also often make mistakes when dividing fractions. Let's take two proper irreducible fractions and divide by each other: (5/6) / (25/33). The student can mix it up and write the resulting expression as (5*25) / (6*33). But this would happen with multiplication, but in our case everything will be somewhat different: (5*33) / (6*25). We reduce what is possible, and the answer will be 11/10. We write the resulting improper fraction as a decimal - 1.1.

Brackets

Remember that in any mathematical expression the order of operations is determined by the precedence of the operation signs and the presence of parentheses. All other things being equal, the order of actions is counted from left to right. This is also true for fractions - the expression in the numerator or denominator is calculated strictly according to this rule.

After all, this is the result of dividing one number by another. If they are not evenly divided, it becomes a fraction - that's all.

How to write a fraction on a computer

Since standard tools do not always allow creating a fraction consisting of two “tiers,” students sometimes resort to various tricks. For example, they copy the numerators and denominators into the Paint graphic editor and glue them together, drawing a horizontal line between them. Of course, there is a simpler option, which, by the way, provides a lot of additional features that will be useful to you in the future.

Open Microsoft Word. One of the panels at the top of the screen is called “Insert” - click it. On the right, on the side where the close and minimize window icons are located, there is a “Formula” button. This is exactly what we need!

If you use this function, a rectangular area will appear on the screen in which you can use any mathematical signs that are not on the keyboard, as well as write fractions in the classic form. That is, dividing the numerator and denominator with a horizontal line. You might even be surprised that such a proper fraction is so easy to write.

Learn math

If you are in grades 5-6, then soon knowledge of mathematics (including the ability to work with fractions!) will be required in many school subjects. In almost any problem in physics, when measuring the mass of substances in chemistry, in geometry and trigonometry, you cannot do without fractions. Soon you will learn to calculate everything in your head, without even writing down the expressions on paper, but more and more complex examples will appear. So learn what a proper fraction is and how to work with it, keep up with your curriculum, do your homework on time, and you will succeed.

The word “fractions” gives many people goosebumps. Because I remember school and the tasks that were solved in mathematics. This was a duty that had to be fulfilled. What if you treated problems involving proper and improper fractions like a puzzle? After all, many adults solve digital and Japanese crosswords. We figured out the rules, and that’s it. It's the same here. One has only to delve into the theory - and everything will fall into place. And the examples will turn into a way to train your brain.

What types of fractions are there?

Let's start with what it is. A fraction is a number that has some part of one. It can be written in two forms. The first one is called ordinary. That is, one that has a horizontal or slanted line. It is equivalent to the division sign.

In this notation, the number above the line is called the numerator, and the number below it is called the denominator.

Among ordinary fractions, proper and improper fractions are distinguished. For the former, the absolute value of the numerator is always less than the denominator. The wrong ones are called that because they have everything the other way around. The value of a proper fraction is always less than one. While the incorrect one is always greater than this number.

There are also mixed numbers, that is, those that have an integer and a fractional part.

The second type of notation is a decimal fraction. There is a separate conversation about her.

How are improper fractions different from mixed numbers?

In essence, nothing. These are just different recordings of the same number. Improper fractions easily become mixed numbers after simple steps. And vice versa.

It all depends on the specific situation. Sometimes it is more convenient to use an improper fraction in tasks. And sometimes it is necessary to convert it into a mixed number and then the example will be solved very easily. Therefore, what to use: improper fractions, mixed numbers, depends on the observation skills of the person solving the problem.

The mixed number is also compared with the sum of the integer part and the fractional part. Moreover, the second one is always less than one.

How to represent a mixed number as an improper fraction?

If you need to perform any action with several numbers that are written in different forms, then you need to make them the same. One method is to represent numbers as improper fractions.

For this purpose, you will need to perform the following algorithm:

  • multiply the denominator by the whole part;
  • add the value of the numerator to the result;
  • write the answer above the line;
  • leave the denominator the same.

Here are examples of how to write improper fractions from mixed numbers:

  • 17 ¼ = (17 x 4 + 1) : 4 = 69/4;
  • 39 ½ = (39 x 2 + 1) : 2 = 79/2.

How to write an improper fraction as a mixed number?

The next technique is the opposite of the one discussed above. That is, when all mixed numbers are replaced by improper fractions. The algorithm of actions will be as follows:

  • divide the numerator by the denominator to obtain the remainder;
  • write the quotient in place of the whole part of the mixed one;
  • the remainder should be placed above the line;
  • the divisor will be the denominator.

Examples of such a transformation:

76/14; 76:14 = 5 with remainder 6; the answer will be 5 whole and 6/14; the fractional part in this example needs to be reduced by 2, resulting in 3/7; the final answer is 5 point 3/7.

108/54; after division, the quotient of 2 is obtained without a remainder; this means that not all improper fractions can be represented as a mixed number; the answer will be an integer - 2.

How to turn a whole number into an improper fraction?

There are situations when such action is necessary. To obtain improper fractions with a known denominator, you will need to perform the following algorithm:

  • multiply an integer by the desired denominator;
  • write this value above the line;
  • place the denominator below it.

The simplest option is when the denominator is equal to one. Then you don't need to multiply anything. It is enough to simply write the integer given in the example, and place one under the line.

Example: Make 5 an improper fraction with a denominator of 3. Multiplying 5 by 3 gives 15. This number will be the denominator. The answer to the task is a fraction: 15/3.

Two approaches to solving problems with different numbers

The example requires calculating the sum and difference, as well as the product and quotient of two numbers: 2 integers 3/5 and 14/11.

In the first approach the mixed number will be represented as an improper fraction.

After performing the steps described above, you will get the following value: 13/5.

In order to find out the sum, you need to reduce the fractions to the same denominator. 13/5 after multiplying by 11 becomes 143/55. And 14/11 after multiplying by 5 will look like: 70/55. To calculate the sum, you only need to add the numerators: 143 and 70, and then write down the answer with one denominator. 213/55 - this improper fraction is the answer to the problem.

When finding the difference, the same numbers are subtracted: 143 - 70 = 73. The answer will be a fraction: 73/55.

When multiplying 13/5 and 14/11, you do not need to reduce them to a common denominator. It is enough to multiply the numerators and denominators in pairs. The answer will be: 182/55.

The same goes for division. To solve correctly, you need to replace division with multiplication and invert the divisor: 13/5: 14/11 = 13/5 x 11/14 = 143/70.

In the second approach an improper fraction becomes a mixed number.

After performing the actions of the algorithm, 14/11 will turn into a mixed number with an integer part of 1 and a fractional part of 3/11.

When calculating the sum, you need to add the whole and fractional parts separately. 2 + 1 = 3, 3/5 + 3/11 = 33/55 + 15/55 = 48/55. The final answer is 3 point 48/55. In the first approach the fraction was 213/55. You can check its correctness by converting it to a mixed number. After dividing 213 by 55, the quotient is 3 and the remainder is 48. It is easy to see that the answer is correct.

When subtracting, the “+” sign is replaced by “-”. 2 - 1 = 1, 33/55 - 15/55 = 18/55. To check, the answer from the previous approach needs to be converted into a mixed number: 73 is divided by 55 and the quotient is 1 and the remainder is 18.

To find the product and quotient, it is inconvenient to use mixed numbers. It is always recommended to move on to improper fractions here.

Common fractions are divided into \textit (proper) and \textit (improper) fractions. This division is based on a comparison of the numerator and denominator.

Proper Fractions

Proper fraction An ordinary fraction $\frac(m)(n)$ is called, in which the numerator is less than the denominator, i.e. $m

Example 1

For example, the fractions $\frac(1)(3)$, $\frac(9)(123)$, $\frac(77)(78)$, $\frac(378567)(456298)$ are correct, so how in each of them the numerator is less than the denominator, which meets the definition of a proper fraction.

There is a definition of a proper fraction, which is based on comparing the fraction with one.

correct, if it is less than one:

Example 2

For example, the common fraction $\frac(6)(13)$ is proper because condition $\frac(6)(13) is satisfied

Improper fractions

Improper fraction An ordinary fraction $\frac(m)(n)$ is called, in which the numerator is greater than or equal to the denominator, i.e. $m\ge n$.

Example 3

For example, the fractions $\frac(5)(5)$, $\frac(24)(3)$, $\frac(567)(113)$, $\frac(100001)(100000)$ are irregular, so how in each of them the numerator is greater than or equal to the denominator, which meets the definition of an improper fraction.

Let us give a definition of an improper fraction, which is based on its comparison with one.

The common fraction $\frac(m)(n)$ is wrong, if it is equal to or greater than one:

\[\frac(m)(n)\ge 1\]

Example 4

For example, the common fraction $\frac(21)(4)$ is improper because the condition $\frac(21)(4) >1$ is satisfied;

the common fraction $\frac(8)(8)$ is improper because the condition $\frac(8)(8)=1$ is satisfied.

Let's take a closer look at the concept of an improper fraction.

Let's take the improper fraction $\frac(7)(7)$ as an example. The meaning of this fraction is to take seven shares of an object, which is divided into seven equal parts. Thus, from the seven shares that are available, the entire object can be composed. Those. the improper fraction $\frac(7)(7)$ describes the whole object and $\frac(7)(7)=1$. So, improper fractions, in which the numerator is equal to the denominator, describe one whole object and such a fraction can be replaced by the natural number $1$.

    $\frac(5)(2)$ -- it is quite obvious that from these five second parts you can make up $2$ whole objects (one whole object will be made up of $2$ parts, and to compose two whole objects you need $2+2=4$ shares) and one second share remains. That is, the improper fraction $\frac(5)(2)$ describes $2$ of an object and $\frac(1)(2)$ the share of this object.

    $\frac(21)(7)$ -- from twenty-one-sevenths parts you can make $3$ whole objects ($3$ objects with $7$ shares in each). Those. the fraction $\frac(21)(7)$ describes $3$ whole objects.

From the examples considered, we can draw the following conclusion: an improper fraction can be replaced by a natural number if the numerator is divisible by the denominator (for example, $\frac(7)(7)=1$ and $\frac(21)(7)=3$) , or the sum of a natural number and a proper fraction, if the numerator is not completely divisible by the denominator (for example, $\ \frac(5)(2)=2+\frac(1)(2)$). That's why such fractions are called wrong.

Definition 1

The process of representing an improper fraction as the sum of a natural number and a proper fraction (for example, $\frac(5)(2)=2+\frac(1)(2)$) is called separating the whole part from an improper fraction.

When working with improper fractions, there is a close connection between them and mixed numbers.

An improper fraction is often written as a mixed number - a number that consists of a whole number and a fraction part.

To write an improper fraction as a mixed number, you must divide the numerator by the denominator with a remainder. The quotient will be the integer part of the mixed number, the remainder will be the numerator of the fractional part, and the divisor will be the denominator of the fractional part.

Example 5

Write the improper fraction $\frac(37)(12)$ as a mixed number.

Solution.

Divide the numerator by the denominator with a remainder:

\[\frac(37)(12)=37:12=3\ (remainder\ 1)\] \[\frac(37)(12)=3\frac(1)(12)\]

Answer.$\frac(37)(12)=3\frac(1)(12)$.

To write a mixed number as an improper fraction, you need to multiply the denominator by the whole part of the number, add the numerator of the fractional part to the resulting product, and write the resulting amount into the numerator of the fraction. The denominator of the improper fraction will be equal to the denominator of the fractional part of the mixed number.

Example 6

Write the mixed number $5\frac(3)(7)$ as an improper fraction.

Solution.

Answer.$5\frac(3)(7)=\frac(38)(7)$.

Adding mixed numbers and proper fractions

Mixed Number Addition$a\frac(b)(c)$ and proper fraction$\frac(d)(e)$ is performed by adding to a given fraction the fractional part of a given mixed number:

Example 7

Add the proper fraction $\frac(4)(15)$ and the mixed number $3\frac(2)(5)$.

Solution.

Let's use the formula for adding a mixed number and a proper fraction:

\[\frac(4)(15)+3\frac(2)(5)=3+\left(\frac(2)(5)+\frac(4)(15)\right)=3+\ left(\frac(2\cdot 3)(5\cdot 3)+\frac(4)(15)\right)=3+\frac(6+4)(15)=3+\frac(10)( 15)\]

By dividing by the number \textit(5) we can determine that the fraction $\frac(10)(15)$ is reducible. Let's perform the reduction and find the result of the addition:

So, the result of adding the proper fraction $\frac(4)(15)$ and the mixed number $3\frac(2)(5)$ is $3\frac(2)(3)$.

Answer:$3\frac(2)(3)$

Adding mixed numbers and improper fractions

Adding improper fractions and mixed numbers reduces to the addition of two mixed numbers, for which it is enough to isolate the whole part from the improper fraction.

Example 8

Calculate the sum of the mixed number $6\frac(2)(15)$ and the improper fraction $\frac(13)(5)$.

Solution.

First, let's extract the whole part from the improper fraction $\frac(13)(5)$:

Answer:$8\frac(11)(15)$.

326. Fill in the blanks.

1) If the numerator of a fraction is equal to the denominator, then the fraction is equal to 1.
2) A fraction a/b (a and b are natural numbers) is called proper if a< b
3) The fraction a/b (a and b are natural numbers) is called improper if a >b or a =b.
4) 9/14 is a proper fraction, since 9< 14.
5) 7/5 is an improper fraction, since 7 > 5.
6) 16/16 is an improper fraction, since 16=16.

327. Write out from the fractions 1/20, 16/9, 7/2, 14/28,10/10, 5/32,11/2: 1) proper fractions; 2) improper fractions.

1) 1/20, 14/23, 5/32

2) 19/9, 7/2, 10/10, 11/2

328. Come up with and write down: 1) 5 proper fractions; 2) improper fractions.

1) ½, 1/3, ¼, 1/5, 1/6

2) 3/2, 4/2, 5/2Yu 6/2, 7/2

329. Write down all proper fractions with a denominator of 9.

1/9, 2/9, 3/9, 4/9, 5/9, 6/9, 7/9, 8/9.

330. Write down all improper fractions with numerator 9.

9/1,9/2, 9/3, 9/4, 9/5, 9/6, 9/7, 9/8, 9/9.

331. Two identical strips were divided into 7 equal parts. Paint 4/7 of one strip and 6/7 of the other.

Compare the resulting fractions: 4/7< 6/7.

Formulate a rule for comparing fractions with like denominators: of two fractions with like denominators, the one with the larger numerator is greater.

332. Two identical strips were divided into parts. One strip was divided into 7 equal parts, and the other into 5 equal parts. Paint 3/7 of the first strip and 3/5 of the second.

Compare the resulting fractions: 3/7< /5.

Formulate a rule for comparing fractions with the same numerators: of two fractions with the same numerators, the one with the smaller denominator is greater.

333. Fill in the blanks.

1) All proper fractions are less than 1, and improper fractions are greater than 1 or equal to 1.

2) Every improper fraction is greater than every proper fraction, and every proper fraction is less than every improper fraction.

3) On a coordinate ray of two fractions, the larger fraction is located to the right of the smaller one.

334. Circle the correct statements.

335. Compare the numbers.

2)17/25>14/25

4)24/51>24/53

336. Which of the fractions 10/11, 16/4, 18/17, 24/24, 2005/207, 310/303, 39/40 are greater than 1?

Answer: 16/4, 18/17, 310/303

337. Arrange the fractions 5/29, 7/29, 4/29, 25/29, 17/29, 13/29.

Answer: 29/29,17/29, 13/29, 7/29, 5/29, 4/29.

338. Mark on the coordinate ray all the numbers that are fractions with a denominator of 5, located between the numbers 0 and 3. Which of the marked numbers are correct and which are incorrect?

0 1/5 2/5 3/5 4/5 5/5 6/5 7/5 8/5 9/5 10/5 11/5 12/5 13/5 14/5

Answer: 1) proper fractions: 1/5, 2/5, 3/5, 4/5.

2) improper fractions: 5/5, 6/5, 7/5, 8/5, 9/5, 10/5, 11/5, 12/5, 13/5, 14/5.

339. Find all natural values ​​of x for which the fraction x/8 is correct.

Answer: 1,2,3,4,5,6,7

340. Find natural expressions for x in which the fraction 11/x will be improper.

Answer: 1,2,3,4,5,6,7,8,9,10,11

341. 1) Write the numbers in the empty cells so that a proper fraction is formed.

2) Write the numbers in the empty cells to form an improper fraction.

342. Construct and label a segment whose length is: 1) 9/8 of the length of segment AB; 2) 10/8 of the length of segment AB; 3) 7/4 of the length of segment AB; 4) the length of the segment AB.

Sasha read 42:6*7= 49 pages

Answer: 49 pages

344. Find all natural values ​​of x for which the inequality holds:

1) x/15<7/15;

2)10/x >10/9.

Answer: 1) 1,2,3,4,5,6; 2) 1,2,3,4,5,6,7,8.

345. Using the numbers 1,4,5,7 and the fraction line, write down all possible proper fractions.

Answer: ¼, 1/5.1/7.4/5.4/7.5/7.

346. Find all natural values ​​of m for which 4m+5/17 is correct.

4m+5<17; 4m<12; m<3.

Answer: m =1; 2.

347. Find all natural values ​​of a for which the fraction 10/a will be improper and the fraction 7/a will be correct.

a≤10 and a>7, i.e. 7

Answer: a = 8,9,10

348. Natural numbers a, b, c and d such that a

The word “fractions” gives many people goosebumps. Because I remember school and the tasks that were solved in mathematics. This was a duty that had to be fulfilled. What if you treated problems involving proper and improper fractions like a puzzle? After all, many adults solve digital and Japanese crosswords. We figured out the rules, and that’s it. It's the same here. One has only to delve into the theory - and everything will fall into place. And the examples will turn into a way to train your brain.

What types of fractions are there?

Let's start with what it is. A fraction is a number that has some part of one. It can be written in two forms. The first one is called ordinary. That is, one that has a horizontal or slanted line. It is equivalent to the division sign.

In this notation, the number above the line is called the numerator, and the number below it is called the denominator.

Among ordinary fractions, proper and improper fractions are distinguished. For the former, the absolute value of the numerator is always less than the denominator. The wrong ones are called that because they have everything the other way around. The value of a proper fraction is always less than one. While the incorrect one is always greater than this number.

There are also mixed numbers, that is, those that have an integer and a fractional part.

The second type of notation is a decimal fraction. There is a separate conversation about her.

How are improper fractions different from mixed numbers?

In essence, nothing. These are just different recordings of the same number. Improper fractions easily become mixed numbers after simple steps. And vice versa.

It all depends on the specific situation. Sometimes it is more convenient to use an improper fraction in tasks. And sometimes it is necessary to convert it into a mixed number and then the example will be solved very easily. Therefore, what to use: improper fractions, mixed numbers, depends on the observation skills of the person solving the problem.

The mixed number is also compared with the sum of the integer part and the fractional part. Moreover, the second one is always less than one.

How to represent a mixed number as an improper fraction?

If you need to perform any action with several numbers that are written in different forms, then you need to make them the same. One method is to represent numbers as improper fractions.

For this purpose, you will need to perform the following algorithm:

  • multiply the denominator by the whole part;
  • add the value of the numerator to the result;
  • write the answer above the line;
  • leave the denominator the same.

Here are examples of how to write improper fractions from mixed numbers:

  • 17 ¼ = (17 x 4 + 1) : 4 = 69/4;
  • 39 ½ = (39 x 2 + 1) : 2 = 79/2.

How to write an improper fraction as a mixed number?

The next technique is the opposite of the one discussed above. That is, when all mixed numbers are replaced by improper fractions. The algorithm of actions will be as follows:

  • divide the numerator by the denominator to obtain the remainder;
  • write the quotient in place of the whole part of the mixed one;
  • the remainder should be placed above the line;
  • the divisor will be the denominator.

Examples of such a transformation:

76/14; 76:14 = 5 with remainder 6; the answer will be 5 whole and 6/14; the fractional part in this example needs to be reduced by 2, resulting in 3/7; the final answer is 5 point 3/7.

108/54; after division, the quotient of 2 is obtained without a remainder; this means that not all improper fractions can be represented as a mixed number; the answer will be an integer - 2.

How to turn a whole number into an improper fraction?

There are situations when such action is necessary. To obtain improper fractions with a known denominator, you will need to perform the following algorithm:

  • multiply an integer by the desired denominator;
  • write this value above the line;
  • place the denominator below it.

The simplest option is when the denominator is equal to one. Then you don't need to multiply anything. It is enough to simply write the integer given in the example, and place one under the line.

Example: Make 5 an improper fraction with a denominator of 3. Multiplying 5 by 3 gives 15. This number will be the denominator. The answer to the task is a fraction: 15/3.

Two approaches to solving problems with different numbers

The example requires calculating the sum and difference, as well as the product and quotient of two numbers: 2 integers 3/5 and 14/11.

In the first approach the mixed number will be represented as an improper fraction.

After performing the steps described above, you will get the following value: 13/5.

In order to find out the sum, you need to reduce the fractions to the same denominator. 13/5 after multiplying by 11 becomes 143/55. And 14/11 after multiplying by 5 will look like: 70/55. To calculate the sum, you only need to add the numerators: 143 and 70, and then write down the answer with one denominator. 213/55 - this improper fraction is the answer to the problem.

When finding the difference, the same numbers are subtracted: 143 - 70 = 73. The answer will be a fraction: 73/55.

When multiplying 13/5 and 14/11, you do not need to reduce them to a common denominator. It is enough to multiply the numerators and denominators in pairs. The answer will be: 182/55.

The same goes for division. To solve correctly, you need to replace division with multiplication and invert the divisor: 13/5: 14/11 = 13/5 x 11/14 = 143/70.

In the second approach an improper fraction becomes a mixed number.

After performing the actions of the algorithm, 14/11 will turn into a mixed number with an integer part of 1 and a fractional part of 3/11.

When calculating the sum, you need to add the whole and fractional parts separately. 2 + 1 = 3, 3/5 + 3/11 = 33/55 + 15/55 = 48/55. The final answer is 3 point 48/55. In the first approach the fraction was 213/55. You can check its correctness by converting it to a mixed number. After dividing 213 by 55, the quotient is 3 and the remainder is 48. It is easy to see that the answer is correct.

When subtracting, the “+” sign is replaced by “-”. 2 - 1 = 1, 33/55 - 15/55 = 18/55. To check, the answer from the previous approach needs to be converted into a mixed number: 73 is divided by 55 and the quotient is 1 and the remainder is 18.

To find the product and quotient, it is inconvenient to use mixed numbers. It is always recommended to move on to improper fractions here.