Question

A pizza parlor has two different sizes of circular pizzas. The smaller one has a diameter of 12 inches and the larger one has a diameter of 20 inches.

What is the ratio of their areas?

I already got the area of each, 113 and 314, but I can't figure out the ratio.

Answer 1

My choices are
9:25
3:5
\[2\sqrt{3}: 2\sqrt{5}\]
\[\sqrt{6}: \sqrt{10}\]

Answer 2

@Whitemonsterbunny17 any idea?

Answer 3

Ooooh, I didn't learn Geometry yet.
But maybe @suckerofmath can help. c:

Answer 4

Oh ok, well thanks anyway :)

Answer 5

I can try

Answer 6

circular pizzas so \[\pi r ^{2}\]

Answer 7

But thats to find the area @Danyboii I already have that. I just need the ratio

Answer 8

oh wait D: i think its smaller over larger

Answer 9

i think since they've mentioned the smaller one first so you have to write the smaller first the n the largest.

Answer 10

Give me 5-7 minutes

Answer 11

Okay @Jesstho.-.

@Danyboii that's what you normally do, put the first over the second \[\frac{ 113 }{ 314 }\]

But you can't really simplify this so that's why I'm thinking its one of the answers with a square root.

Answer 12

We know that the diameter of the smaller pizza is 12 inches, so the radius should be 6 inches right?

Answer 13

Yeah

Answer 14

and we know that the area of a circle is pi*r^2, right?

Answer 15

Yeah and that'll give you 113

Answer 16

So are of the smaller pizza should be pi*6^2 = pi*36=36*pi

Answer 17

So it's area should be pi*10^2= 100*Pi

Answer 18

Now ratio of the areas of two pizzas canceling out pis
It becomes 35/100
Which is equal to 9/25
and that's out answer

Answer 19

I hope you understood that

Answer 20

Oh okay, yeah I got it. Thank you!

Answer 21

You're welcome

Answer 22

oh so didnt find the radius XD was going to explain u that earlier but u said u found the area XD oh well :3