40 fifth graders take a bus to school. 8x8= 64 so they have you a good fraction to start with to find out how many kids are walking or taking their bike (3/8) all you have to do is multiply 3 and 8 which equals 24 to find the fraction of the amount of kids who take the bus you subtract 3 from 8 which gives 5/8 and to get the answer you multiply 5 and 8 which is 40.