The Formula for the Volume of the Pyramid is V=1/3BxH which B is the area of the Base. In this case... A of the Base is A=8x6 which is A=48cm2 and the H=5cm.
to get 35 red cars you would need to multiply the 7 red cars by 5, so u would do the same with the blue cars. The 2 blue cars multiplied by 5 would be 10 blue cars.