Henry has two same size rectangle divided into the same number of equal parts. one rectangle has 2/5 of the parts shaded, and the other has 1/2 of the parts shaded. Into how many parts could each rectangle be divided? show the work

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?