Question

(1) Volume of the cone is 6280 cm and its base radius is 20 cm. Find its perpendicular height.
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Answer 1

Required Answer :

The perpendicular height of the cone = 14.98 cm

Given :

• Volume of cone = 6280 cm³

• Base radius of the cone = 20 cm

To find :

• Perpendicular height of the cone

Solution :

Formula of volume of cone :

• Volume of cone = ⅓ πr²h

Where,

• Take π = 22/7

• r denotes the radius

• h denotes the height

We have,

• r = 20 cm

• volume = 6280 cm³

Substituting the given values :

→ 6280 = 1/3 × 22/7 × (20)² × h

→ 6280 = 1/3 × 22/7 × 20 × 20 × h

→ 6280 = 8800/21 × h

→ 6280 × 21/8800 = h

→ 628 × 21/880 = h

→ 314 × 21/440 = h

→ 157 × 21/220 = h

→ 3297/220 = h

→ 14.98 = h

Therefore, the perpendicular height of the cone = 14.98 cm

Figure :

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