By taking the quotient between the volumes, we conclude that he must use the blue cup 16 times or the green cup 4 times.
How many times does he need to use each cup?
The volume of the sink is 512π in^3.
The blue cup is a cylinder of diameter = 4 in and a height = of 8 in, then its volume is:
V = π*(4in/2)^2*8in = 32π in^3
The number of times that he needs to use this cup is given by:
N = (512π in^3)/(32π in^3) = 512/32 = 16
He needs to use 16 times the blue cup.
The green cup has a diameter =of 8in and a height = of 8in, then its volume is:
V' =π*(8in/2)^2*8in = 128π in^3
The number of times that he must use this cup is:
N' = (512π in^3/ 128π in^3) = 512/128 = 4
He needs to use 4 times the green cup.
hope it helps
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