Mathematics S2 Ch.11 Areas and Volumes II

Question

Information

Water flows from a pipe into an empty right circular cylinder tank with curved surface area 4000π cm²

and height 80cm

The base radius of the tank is 25cm

Q. Cindy claims that it takes less than 30minutes to fill up the tank if the rate of water flow is 2000π cm³cm/min. Do you agree? Explain your answer.

A. Yes

Answer 1

surface area of a cylinder = 4000pi cm

height = 80 cm

base radius = 25 cm

base area = pi(r^2) = pi(25^2 = 625pi

volume = Base area times height = 625pi x 80 = 50,000 cm^3

at 2,000 per minute that's 50,000/2,000 = 50/2 = 25 minutes

She's a little off, but close. 25 not 30 minutes to fill it up