A jar of peanut butter which is 3 inches in diameter and 4 inches high sells for $0.60. At the same rate, what would be the price for a jar that is 6 inches in diameter and 6 inches high?

Answer 1

volume of first jar
= π(1.5)^2 (4) = 9π inches^3

volume of 2nd jar
= π(3^2)(3) = 27π
which is 3 times the volume of the first, so it should cost 3 times as much
3(0.60) = $1.80

Answer 2

I do not get how you got 3times as much when they aren't fully simplified.