## anonymous one year ago ***WILL MEDAL AND FAN*** A 10" diameter pumpkin pie is cut into six equal servings. What is the area of the top of each piece of pie? a) 3.33pi inches b) 4.17pi inches c) 16.66pi inches

1. anonymous

im thinking its A cause im trying to work it out but it just comes close to ten

2. phi

10 inch diameter means 5 inch radius Do you know how to find the area of a circle with r=5 ?

3. anonymous

Yea. The area would be 78.5 right?

4. anonymous

@phi

5. phi

I would not make it decimal (because the answer choices have "pi" in them can you find the area, but do not change pi to a decimal?

6. anonymous

Hmmm`

7. phi

first, what is the formula for Area of a circle?

8. anonymous

pi x radius squared

9. phi

and r= 5 r squared ( $$r^2$$ ) = 5*5= 25 so Area= 25 * 3.14159265358979323846264338327950288419716939937510582097494459230781640628620899862803482534211706798214808651328230664709384460955058... pi goes on forever... rather than truncating to approximately 3.14 (which is close but not exactly correct, as you can see), and rather than typing all those numbers (which you can't because they go on forever), people just say... call that number pi Area= $$25 \pi$$ and let's not multiply it out unless you want a decimal number... and you can use as many digits of pi as makes sense for your problem (i.e. how accurate you want to be)

10. phi

so the area of the circle is 25pi now divide that area into 6 equal pieces. what is the area of 1/6 of the whole circle? can you do that ? (and leave pi alone)

11. anonymous

It's 4.6

12. phi

it's $\frac{25\pi}{6}$ which is the same as $\frac{25}{6} \pi$ (hopefully that makes sense... if not you should learn why you can do that ) now what is 25/6 ?

13. anonymous

4.16

14. phi

you mean 4.16666... (the 6 repeats) if you round to the nearest 100th (2nd decimal to the right of the decimal point) you get 4.17 now you can answer the question

15. anonymous

Oh thanks so much. and btw, can you answer another question for me? Just one more/

16. anonymous

?

17. anonymous

18. phi

Please make a new post.

19. anonymous

I will