## muscrat123 one year ago The volume of a cone is 251.2 cubic inches. The height of the cone is 15 inches. What is the radius of the cone, rounded to the nearest inch? Use π = 3.14. 16 inches 8 inches 6 inches 4 inches

1. muscrat123

@dan815

2. sepeario

What we have to do with this question is work backwards. Do you know the formula to find the volume of a cone?

3. muscrat123

yes. i know that i have to work backwards, i just got an answer not an answer choice

4. sepeario

5. muscrat123

idek!

6. sepeario

Okay let me show you how I would do it. Volume of cone = $\frac{ 1 }{ 3 }\pi r^2 h$ (where r is radius and h is height).

7. sepeario

So we could just substitute the values we already have to find the values that are unknown; $251.2=\frac{ 1 }{ 3 } 3.14 * r^2*15$

8. sepeario

I'm sorry if that's a bit hard to read but do you understand so far?

9. muscrat123

yes

10. muscrat123

@Sepeario

11. sepeario

Then we have $251=3.14/3 * 15 * r^2$ $251=(3.14*15)/3 * r^2$ $251=15.7r^2$

12. sepeario

$251/15.7=r^2$ The radius squared approximately equals 16, and the radius hence is 4.

13. muscrat123

14. sepeario

Yes.

15. muscrat123

so d?