1/5 + 2/5

5 Answers

tiburtius's profile pic

tiburtius | High School Teacher | (Level 2) Educator

Posted on

To add two fractions we first need to find common denominator. We can do that by finding least common multiple or, if you are not sure how to do that, you can simply multiply the two denominators. But, that way you will be working with bigger numbers.

However, this case is much simpler because the denominators are already the same so we simply copy the denominator and add the numerators.


Therefore the solution is `3/5.`

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spolak | (Level 1) Adjunct Educator

Posted on

In order to add fractions, we must have fractions with the same type of name.

Fractions are named based on their denominator  (or the bottom number). 

So if we consider '1/4', this fraction's name is of the 'fourths' variety.

If we consider '3/20', this fraction's name is of the 'twentieths' type.

Since the initial question has two fractions of the same type of name, we need to only add the numerators while keeping their name (or denominator the same). So our answer would be 1/5 + 2/5 = 3/5.

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labellavita89 | High School Teacher | (Level 1) Adjunct Educator

Posted on

To be able to add or subtract fractions, the denominator (# on the bottom) needs to be the same. In this problem the denominators are the same already, so you can add them together. When adding or subtracting fractions, you just add or subtract the numerators (#s on the top) together and the denominator says the same. 

`1/5 + 2/5 = 3/5`

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middleschool-teacher's profile pic

middleschool-teacher | Middle School Teacher | (Level 1) Adjunct Educator

Posted on

(1/5) and (2/5) are like fractions which means they have the same denominator.  To add these to fractions, you then add the top numbers (the numerators).  (1/5) + (2/5) = (3/5).  (3/5) is the answer in its simplest form because 3 and five do not have common factors.  

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rsarvar1a | Student, Grade 9 | (Level 1) Honors

Posted on

Adding fractions is like adding any other numbers together. However, there's one thing that we have to pay attention to: denominators.

For example, with 1/5 + 2/5, the denominators (the second, or bottom, number) are the same, which means we keep the denominator the same and add the top numbers, or numerators, together, to get 3/5.

If we had fractions like 3/4 and 1/8, we can't just add the numerators because the denominators aren't the same. We would first have to find a common denominator. The denominators from before (4 and 8) have a common multiple of 8. Since we multiplied the 4 by 2 to get 8, we do the same to the numerator.

Now, we have 6/8 (3*2 / 4*2) and 1/8.

We can just add the numerators now, to get 7/8.