It takes 200 pieces to pave the floor of the study with 15cm long square bricks. How many pieces do you need to use 25cm long square bricks instead?

It takes 200 pieces to pave the floor of the study with 15cm long square bricks. How many pieces do you need to use 25cm long square bricks instead?

15x200x15 = 45000 square centimeter
45000 / (25 * 25) = 72 pieces
You need 72 yuan for the 25cm side
2 use the equation to set X blocks with side length of 25cm
15*15*200=25*25*x
X = 72
You need 72 yuan for the 25cm side