Question

If the circumference of a circle of radius r inches is equal to the perimeter of a square with aside length of s inches so r/s=?

Answer 1

Do you have the formula for the circumference of a circle?

Answer 2

Yes 2pi\[^{2}\]

Answer 3

almost... it's 2 π r like 2 times pi times the radius.

Answer 4

And what is the perimeter of the square with sides that are "s" inches each? You won't have a number, but just add up each of the 4 sides with length "s"... you get "4s"

Are you with me so far?

Answer 5

yes

Answer 6

This problem says the the circle's circumference is equal to the square's perimeter.

Let's write an equation that shows they are equal...

Answer 7

2πr = 4s

Does that make sense? You have circumference on the left, and perimeter on the right.

Answer 8

yes

Answer 9

Ok, so the last thing the problem asks is, what is r / s ?

You need to take that equation and shift things around until you have r/s on one side of the equation... then it equals the stuff on the other side.

2πr = 4s ----->>>> r/s = ???

Answer 10

im confused what to do when i get pi r divided by s =2

Answer 11

Try to do the next step... you might divide both sides by "s".... that way you would at least have an "r/s" with some other stuff on the left side... it's a decent start.

Answer 12

is that what you get?
π r/s = 2

Answer 13

yes

Answer 14

You're almost done :)

Now divide both sides by π to leave r/s all alone on the left side

Answer 15

r/s = 2/π If you need to show it as numbers, hopefully they told you how to estimate "pi"... like if they said "estimate pi as 3.14", then you can do 2/3.14 as the solution. Otherwise, just leave it as 2/π

Answer 16

So you don't really know or even need to know what "r" and "s" were... you just found their ratio, just like the problem asked...

It was just a matter of writing the formulas for each, setting them equal, and then simplifying.