Sum of Fractions

๐Ÿ†Practice addition of fractions

To add fractions, we must find the common denominator simplifying, expanding, or multiplying the denominators.
Then, you only need to add the numerators to get the result.

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\( \)\( \frac{4}{5}+\frac{1}{5}= \)

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Sum of Fractions

In this article, you will learn the easiest ways to add fractions, this will allow you to add all kinds of fractions without any inconvenience.
Shall we start?

The first step to solving a fraction addition is to find the common denominator.
Getting a common denominator means that we end up with two fractions with the same denominator. We will do this by simplifying, expanding, or multiplying the denominators.
After finding the common denominator, we will continue with the second step.
The second step to solving a fraction addition is to add the numerators.
We may encounter different cases of additions that we will study next:


First case:

One of the denominators that appear in the initial exercise will be the common denominator.

Sometimes we will encounter quite simple fractions where we won't need to expand or simplify both, but only one of the fractions.
Let's see an example:

32+14=\frac{3}{2}+\frac{1}{4}=

Upon observing these denominators, we will immediately realize that, if we multiply the denominator 22 by 22, we will reach the denominator 44.
This way, we will reach the common denominator and will be able to solve the exercise easily.

Observe -> When multiplying the denominator to transform it into the common denominator, we must also multiply the numerator by the same number so that the value of the fraction does not change.

We will do this by expanding by 22 and we will obtain:

64+14=\frac{6}{4}+\frac{1}{4}=

Now let's move to the second step and add the numerators.
Attention โ€“> We do not add the denominators. Once we reach the common denominator, only the numerators are added, which, in fact, have the same denominator.



Let's see it in an exercise:

64+14=74\frac{6}{4}+\frac{1}{4}=\frac{7}{4}

We add 1+61+6 and leave the denominator only once.

If we wish, we can simplify the fraction and write it as follows: 1341\frac{3}{4}

Another exercise:

13+26=\frac{1}{3}+\frac{2}{6}=

Solution:
We will realize that, if we multiply 33 by 22 we will reach 66 and, this will be the common denominator.

We will obtain:

โ€‹โ€‹26+26=โ€‹โ€‹\frac{2}{6}+\frac{2}{6}=

Let's add the numerators and we will obtain:
46\frac{4}{6}
We can simplify and arrive at: 23\frac{2}{3}


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Second case:

The common denominator will be the product of the given denominators.

Sometimes we will encounter slightly more complicated exercises in which it will not be enough to expand a single fraction to obtain the common denominator, but rather, we must intervene in both fractions.
Do not worry, the way to act in such a case is simply to multiply the first fraction by the denominator of the second and multiply the second fraction by the denominator of the first.

See how simple this is:

A1. Sum of fractions

Let's multiply the denominators:
We will multiply the 25\frac{2}{5} by 44 (the denominator of the second fraction) and the 14\frac{1}{4}ย by 55 (the denominator of the first fraction).
We will obtain:
820+520=\frac{8}{20}+\frac{5}{20}=

Let's add the numerators and we will arrive at the solution:
1320\frac{13}{20}
Did you see how simple it was? This is a technical method that does not require us to think about how to reach the common denominator.
Therefore, we recommend using it in all fraction addition exercises.


Third case:

Sum of 33 fractions

In case there are 33 fractions with different denominators in the exercise, we will first find a common denominator for 22 of them (the simplest ones), then we will find the common denominator between the one we obtained and the third given fraction.

Let's see an example and you'll see it's very simple:
210+23+45=\frac{2}{10}+\frac{2}{3}+\frac{4}{5}=
Let's look at the denominators and ask ourselves - Among the three denominators, which pair of them is easier to find a common denominator for?
The answer is 55 and 1010, since 1010 is the common denominator for both.
Therefore, we will multiply 45\frac{4}{5} by 22 and we will get:
210+23+810=\frac{2}{10}+\frac{2}{3}+\frac{8}{10}=
Now we can add the numerators that already have a common denominator to arrive at a clearer and more orderly exercise (this step is not mandatory, but it will help us later.

A2 - Sum of fractions

Now we just have to find the common denominator between 1010 -> the new denominator we found, and 33 the third denominator of the exercise.
We will do this with the method of multiplying denominators and we will get:
3030+2030=\frac{30}{30}+\frac{20}{30}=
Let's add the numerators and we will get:
5030\frac{50}{30}
We can simplify and arrive at:
53=123\frac{5}{3}=1\frac{2}{3}


Examples and exercises with solutions for adding fractions

Exercise #1

58+18= \frac{5}{8}+\frac{1}{8}=

Video Solution

Step-by-Step Solution

To solve the problem of 58+18 \frac{5}{8} + \frac{1}{8} , follow these steps:

  • Step 1: Identify that both fractions have the same denominator: 8.
  • Step 2: Since the denominators are the same, add the numerators to get a new numerator: 5+1=6 5 + 1 = 6 .
  • Step 3: The resulting fraction is 68 \frac{6}{8} .
  • Step 4: Simplify the fraction if needed; 68 \frac{6}{8} simplifies to 34 \frac{3}{4} , which is a reduced form.

Therefore, the solution for the fraction addition 58+18 \frac{5}{8} + \frac{1}{8} is 68 \frac{6}{8} , which simplifies to 34 \frac{3}{4} , but considering the choices given, the answer choice corresponds to 68 \frac{6}{8} , which is choice 3.

Answer

68 \frac{6}{8}

Exercise #2

14+34= \frac{1}{4}+\frac{3}{4}=

Video Solution

Step-by-Step Solution

To solve the problem of adding the fractions 14 \frac{1}{4} and 34 \frac{3}{4} , we can follow these steps:

  • Step 1: Identify that both fractions share the same denominator of 4.
  • Step 2: Add the numerators directly: 1+3=4 1 + 3 = 4 .
  • Step 3: Retain the common denominator, giving us 44 \frac{4}{4} .
  • Step 4: Simplify the result, 44=1 \frac{4}{4} = 1 .

Therefore, the sum of 14 \frac{1}{4} and 34 \frac{3}{4} is 1 1 .

Answer

1 1

Exercise #3

18+68= \frac{1}{8}+\frac{6}{8}=

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify that both fractions have the same denominator.
  • Step 2: Add the numerators of the two fractions.
  • Step 3: Keep the common denominator unchanged.
  • Step 4: Express the result as a simplified fraction if necessary.

Now, let's work through each step:
Step 1: Both fractions are 18\frac{1}{8} and 68\frac{6}{8}, with a common denominator of 8.
Step 2: Add the numerators: 1+6=71 + 6 = 7.
Step 3: Use the common denominator to create the sum: 78\frac{7}{8}.
Step 4: The fraction 78\frac{7}{8} is already in its simplest form, as 7 and 8 have no common factors other than 1.

Therefore, the solution to the problem is 78 \frac{7}{8} .

Answer

78 \frac{7}{8}

Exercise #4

19+29= \frac{1}{9}+\frac{2}{9}=

Video Solution

Step-by-Step Solution

To solve the problem of adding the fractions 19 \frac{1}{9} and 29 \frac{2}{9} , we proceed with the following steps:

  • Step 1: Verify that the fractions have the same denominator.
    Both fractions, 19 \frac{1}{9} and 29 \frac{2}{9} , have a common denominator of 9.
  • Step 2: Add the numerators.
    The numerators are 1 and 2, respectively. So, 1+2=3 1 + 2 = 3 .
  • Step 3: Write the result over the common denominator.
    This gives us the fraction 39 \frac{3}{9} .
  • Step 4: Simplify the fraction if possible.
    The fraction 39 \frac{3}{9} can be simplified by dividing the numerator and the denominator by their greatest common divisor, which is 3: 39=3รท39รท3=13 \frac{3}{9} = \frac{3 \div 3}{9 \div 3} = \frac{1}{3}

Therefore, the solution to the problem is 13 \frac{1}{3} .

Answer

13 \frac{1}{3}

Exercise #5

24+14= \frac{2}{4}+\frac{1}{4}=

Video Solution

Step-by-Step Solution

To solve this problem, let's follow these steps:

  • Step 1: Identify that both fractions 24\frac{2}{4} and 14\frac{1}{4} have the same denominator.
  • Step 2: Add the numerators together while keeping the denominator the same.
  • Step 3: Simplify the resulting fraction if possible.

Now, let's perform these steps:

Step 1: The denominator for both fractions is 4, so we can proceed with addition.

Step 2: Add the numerators: 2+1=32 + 1 = 3.

Step 3: Place the result over the common denominator: 34\frac{3}{4}.

Therefore, the result of adding 24+14\frac{2}{4} + \frac{1}{4} is 34\frac{3}{4}.

This matches the correct choice, which is 34\frac{3}{4}.

Answer

34 \frac{3}{4}

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