Question

A construction company was contracted to build a cylindrical storage tank with a diameter of 60 feet and height of 16 feet. Just before construction was to begin, it was learned that a new law allows tanks to be a maximum of 9 feet in height.
If the tank is redesigned to meet the law, but has the same volume, what is its new diameter?
a.)106 feet, 8 inches
b.)80 feet
c.)40 feet
d.)53 feet, 4 inches

Answer 1

V=pi r^2 h, v=pi 30^2 16
v= pi r^2 9
v=v
p r^2 9 = pi 30^2 16 Divide thru by pi
r^2 9 =30^2 16
r^2 =(30^2 16)/9=1600
r=sq rt 1600
r=_______

Answer 2

I got 40 feet. Is that correct?

Answer 3

Compute r and double to get diameter as the question is asking for diameter.

Answer 4

Oh okay.

Answer 5

The radius is indeed 40 feet

Answer 6

Compute the diameter.

Answer 7

So it's 80 for the diameter!

Answer 8

Your calculations and reasoning is good.

Answer 9

Thank you so much! :)

Answer 10

You're welcome hope you followed with understanding, did you see how we didn't have to mess with the irrational pi?

Answer 11

Yes ahaha

Answer 12

Good luck in your studies.

Answer 13

Thanks