PROBLEM
surface area and volume
Coffee is sold in two different-sized canisters. The smaller canister has a diameter of 9 cm and a height of 12 cm. The larger canister is double the size of the small canister. Calculate the volume and surface area of each canister and compare the results of doubling the dimensions.
Coffee is sold in two different-sized canisters. The smaller canister has a diameter of 9 cm and a height of 12 cm. The larger canister is double the size of the small canister. Calculate the volume and surface area of each canister and compare the results of doubling the dimensions.
SOLUTION
Volume: V = πr2h
Surface Area: SA = 2πr2 + 2πrh
Radius: r = d/2
rsmall = (9/2) cm
hsmall = 12 cm
rlarge = 9 cm
hlarge = 24 cm
Vsmall = π(9/2)2(12) = 243π cm3
SAsmall = 2π(9/2)2 + 2π(9/2)(12) = (81/2)π + 108π = (170/2)π cm2
Vlarge = π(9)2(24) = 1944π cm3
SAlarge = 2π(9)2 + 2π(9)(24) = 162π + 432π = 594π cm2
SAlarge = 2π(9)2 + 2π(9)(24) = 162π + 432π = 594π cm2