Two crates, 10 kg and 15 kg respectively, are connected with a thick rope according to the diagram. A force, to the right, of 500 N is applied. The boxes move with an acceleration of 2 m/s^2 to the right. One third of the total frictional force is acting on the 10 kg block and two thirds on the 15 kg block. Calculate: the magnitude and direction of the total frictional force present.