Question

Estimate the circumference. Use 3.14 or 22/7 to approximate π.

http://prntscr.com/a3o3z7

A.
18.75 cm

B.
19.63 cm

C.
37.5 cm

D.
39.25 cm

Answer 1

What you are provided with is diameter
However the formula for area = pi *radius*radius
and radius = diameter/2
Can you work out the value of area now?

Answer 2

Im a little bit confused... :3

Answer 3

I can't view the screenshot.

Answer 4

ohh.. hold on a sec!

Answer 5

Thank you :)

So, to find the circumference, you have to use the formula 2πr.
The diameter is 12.5cm. Half of the diameter is radius. What is the radius?
(Hint: Do 12.5 divided by 2)

Answer 6

6.25, right? XD

Answer 7

Yes :)

Now we can plug in 6.25 for "r"

2*π*6.25

Answer 8

I put that in the calculator, and it gave me 39.2699081699 :3

Answer 9

Thank you so much! Its D!! ^3^

Answer 10

Lol we can just round it to 39 :)

Congratulations, you found the circumference!

Answer 11

Thank you!!

Answer 12

No problem :)