Question

The volume of a right circular cone with both

Answer 1

Question:

The volume of a right circular cone with both diameter and height equal to h is 250/7 cm³.

What is the value of h?

Answer:

A. 5

Step-by-step explanation:

Given

Solid Shape: Cone

Volume = 250/7

Diameter = Height

Required

Find the height of the cone

Provided that the diameter (D) and the height (h) are equal; This implies that

D = h ------ (1)

Also, Diameter (D) = 2 * Radius (r)

D = 2r

Substitute 2r for D in (1)

2r = h

Multiply both sides by ½

½ * 2r = ½ * h

r = ½h

Volume of a cone is calculated by;

Volume = ⅓πr²h

⅓πr²h = 250/7

Substitute ½h for r

$\frac{1}{3} * \pi * (\frac{1}{2}h)^2 * h = \frac{250}{7}$

Take π as 22/7, the expression becomes

$\frac{1}{3} * \frac{22}{7} * (\frac{1}{2}h)^2 * h = \frac{250}{7}$

Open the bracket

$\frac{1}{3} * \frac{22}{7} * \frac{1}{4}h^2 * h = \frac{250}{7}$

Multiply both sides by 7

$7 * \frac{1}{3} * \frac{22}{7} * \frac{1}{4}h^2 * h = \frac{250}{7} * 7$

$\frac{1}{3} * 22 * \frac{1}{4}h^2 * h = 250$

Multiply both sides by 3

$3 * \frac{1}{3} * 22 * \frac{1}{4}h^2 * h = 250 * 3$

$22 * \frac{1}{4}h^2 * h = 750$

Multiply both sides by 4

$4 * 22 * \frac{1}{4}h^2 * h = 750 * 4$

$22 * h^2 * h = 3000$

$22 * h^3 = 3000$

Divide both sides by 22

$h^3 = \frac{3000}{22}$

$h^3 = 136.36$

Take cube root of both sides

$h = \sqrt[3]{136.36}$

$h = 5.15$

$h = 5$ (Approximated)