You are a school photographer taking individual and class pictures for 2 classes of 21 students each. on average, each individual picture takes 3 minutes and a class picture takes 10 minutes. about how long should it take you to take all of the pictures?

Two cars which are 40 miles apart start moving simultaneously in the same direction with constant speeds. if the speed of the car which is behind is 56 mph and the speed of the other car is 48 mph, how many hours will it take for the car which is behind to catch up the car ahead of it?