It takes April 7 1/3 hours to drive to her grandparents' house. So far she has driven 3 5/6 hours. How many more hours does April need to drive?

First you have to take the mixed numbers and turn them into common fractions

22/3 and 23/6

then you take the 22/3 and multiply it by 2 so that the two fractions have the same denominator

44/6 then you have to subtract 23/6 from 44/6 and turn it back into a mixed number

44/6-23/6 = 21/6---> 3 3/6 - - - > 3 1/2

April has to drive for 3 1/2 more hours to get to her parent's house