The question
A granite cube is 10 times that of another granite cube. The pressure exerted by the larger cube on its base is how many times more the pressure exerted by the smaller cube on its base?
Well I guess you mean the weight is 10 times the little one
say the big one is 1 m on a side, vol = 1
so
vol /surface area of bottom = 1
little one volume = .1
so side = .1^(1/3)
bottom area = .1^2/3
vol/surface area = .1/(.1^(2/3))
ratio = 1/ [.1/(.1^(2/3))]
= .1^(2/3)/.1^(1) = .1^-(1/3)
=2.15