This is a subtraction problem so subtract 3/4 from 7/8 (7/8 - 3/4). First you have to make them both have the least common denominator. That is 8. So multiply both the numerator and denominator or 3/4 by 2. 3 x 2= 6 and 4 x 2= 8. New fraction is 6/8. Now solve problem again with new fraction. 7/8 - 6/8= 1/8. Your answer is 1/8