Question

help pweaseee D:


Andy has two similar conical hats, Hat A and Hat B. The diameter of Hat A is 18 inches, and the diameter of Hat B is 9 inches. What is the ratio of the volume of Hat A to the volume of Hat B?

2:1
16:1
4:1
8:1

Answer 1

Volume of a cone is \[\pi*r ^{2}*h/3\]

Answer 2

And diameter is just 2r, so for hat A r=9 in and hat B r=4.5 in

Answer 3

im following :)

Answer 4

Set up an equation that has volume on both sides like so:
\[\pi*r _{A}^{2}*h/3=\pi*r _{B}^{2}*h/3\]

Answer 5

As you can see, the pi and h/3 will cancel out once you divide both sides by them. Then you are left with r^2 on each side for the respective cones.

Answer 6

And you can take it from there =P

Answer 7

ok one sec :D

Answer 8

so it would be..
\[9^2 = 4.5^2\]
which will simplify to \[4:1\] ? :D

Answer 9

smarty pants :3

Answer 10

X'D

Answer 11

thanks guys :))

Answer 12

Yeah you got it!

Answer 13

Every ratio type problem can be handled this way

Answer 14

alright thank you so much :))

Answer 15

it wasnt 4:1 :( .. oh well thanks though :)

Answer 16

XDD

Answer 17

:O oha! how so?

Answer 18

Hmm is it not? Let me plug everything in myself

Answer 19

no idea @annas and @nuttyliaczar no worries its fine , unless u want to check it :3

Answer 20

I just checked and still got 4:1

Answer 21

i'll asj my teacher, thanks anyways :)

Answer 22

annas cookies *_*

Answer 23

Volume for A = pi*r^2*h/3 = 254.469*h/3
Volume for B = pi*r^2*h/3 = 63.617*h/3

Answer 24

Dividing them gives 4/1 so... I'm not sure why that was wrong

Answer 25

its ok i'll talk to my teacher :) thanks though i really appreciate ur help guys :)