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3 years ago

7

The volume of a cone is 62.8 cubic inches. The height of the cone is 15 inches. What is the radius of the cone, rounded to the n

earest inch? Use π = 3.14.
A 2 inches
B 4 inches
C 8 inches
D 9 inches

2 answers:

Contact [7]3 years ago

5 0

Step-by-step explanation:

$\pi {r}^{2} \frac{h}{3} = V \\ \\ \pi {r}^{2} \frac{15}{3} = 62,8 \\ \\ \pi {r}^{2}(5) = 62,8 \\ \\ 5\pi {r}^{2} = 62,8 \\ \\ 3,99797217 ≈ \frac{62,8}{5\pi} \\ \\ 3,99797217 ≈ {r}^{2} \\ \\ 1,999492978 ≈ r \\ \\ 2 ≈ r$

I am joyous to assist you anytime.

Setler79 [48]3 years ago

3 0

R = sqrt 3 * (V /( pi * h))
V = 62.8
pi = 3.14
h = 15
now we sub
R = sqrt 3 * (62.8 / (3.14 * 15)
R = sqrt 3 * (62.6 / 47.1)
R = sqrt 3 * 1.33
R = sqrt 3.99
R = 1.9 rounds to 2 inches <===

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