Question

THE HEIGHT AND THE SLANT HEIGHT OF A CONE ARE 21 CM AND 28 CM RESPECTIVELY. FIND THE VOLUME OF THE CONE.

Answer 1

Answer:

• 7546 cm³.

Step-by-step explanation:

Using the relation,

➝ r = √l² - h²

• √28² - 21²
• √784 - 441
• √343
• 7√7 cm

Volume of cone,

➝ 1/3πr²h

• 1/3 × 22/7 × 7√7 × 7√7 × 21
• 7546 cm³

Answer 2

Given :-

The height and slant height of cone are 21 cm and 28 cm

To Find :-

Volume

Solution :-

We know that

l² = r² + h²

(28)² = r² + (21)²

784 = r² + 441

r² = 784 - 441

r² = 343

r = √343

r = 18.5 cm

Now

Volume = 1/3 × π × r² × h

Volume = 1/3 × 22/7 × (18.5)² × 21

Volume = 1/3 × 22 × 342.25 × 3

Volume = 22 × 342.25

Volume = 7,529.5 cm³