A group of 72 students went on a field trip . The students traveled in vans , with an equal amount of boys and girls in each van . If 42 boys went on the trip ,how many vans were there?
There were 6 vans because, if there were 42 boys and 72 children, there were 30 girls, and the highest common factor of 30 and 42 is 6. In each van, there were 5 girls (because 5 x 6 = 30) and 7 boys (because 7 x 6 = 42).
