For example, if you are asked to add 2/5 and 1/3, you would find the smallest number that both numbers divide into… in this case, it is 15.

So set it up as x/15 and y/15. 5 goes into 15 three times, so multiply 3 by 2 and get 6/15. So 2/5 is same as 6/15. Do same for other and realize 1/3 is same as 5/15.

Then add 6 and 5 together and get 11.

So 2/5 + 1/3 = 11/15, and this does not simplify so your answer is 11/15.

5/7+2/9

you have to find a common denominator…so find a number that both 7 and 9 are factors (?) of. the easiest way to do it is to multiply 5/7 by 9/9 and multiply 2/9 by 7/7. (you have to multiply by 9/9 or 7/7 so that the value of the fraction stays the same…sine both 9/9 and 7/7 equal 1, multiplying the fractions by them wont actually change their values)

so after multiplying the fractions, you end up with

45/63+14/63=59/63

then if its possible, simplify the fraction

4/7 + 2/3

7 x 3 = 21 and 7 x 2 = 14

4/7 + 14/21

3 x 7 = 21 and 3 x 4 = 12

12/21 + 14/21 = 26/21 = 1 5/21

I hope this helped.