Easy. Okay. We are trying to find out how much of the pizza they both ate together. To do this we need a common denominator. A common denominator of 3/4 and 1/8 are 8. We don't need to convert 1/8 because it already has 8 as the denominator. So we convert 3/4 into a fraction that has a fraction with a denominator of 8. We multiply both the numerator and denominator by 2 which means 3/4 is equal to 6/8. Now all we have to do is 6/8 + 1/8 which we get 7/8. So the answer is 7/8. I hope this helps.
