Question

.A joker’s cap is in the form of cone of base radius 7cm and height 24 cm. Find the area of the sheet to make 10 such caps. write simple answer please .

Answer 1

Given :

• A joker’s cap is in the form of cone of base radius 7cm and height 24 cm.

To Find :

• The area of the sheet to make 10 such caps = ?

Solution :

• Radius of cone = 7 cm
• Height of cone = 24 cm

First of all we need to find the Slant Height of the cone :

→ Slant Height = √(Radius)² + (Height)²

→ Slant Height = √(7)² + (24)²

→ Slant Height = √49 + 576

→ Slant Height = √625

→ Slant Height = 25 cm

• Hence,the slant height of the cone is 25 cm.

Now,let's find the lateral surface area of cone :

→ CSA of cone = πrl

→ CSA of cone = 22/7 × 7 × 25

→ CSA of cone = 22 × 25

→ CSA of cone = 550 cm²

• Hence,the area of the sheet to make 1 such caps is 550 cm².

Finding area of the sheet to make 10 such caps :

→ CSA of 10 cones = 10 × πrl

→ CSA of 10 cones = 10 × 550

→ CSA of 10 cones = 5500 cm²

• Hence,the area of the sheet to make 10 such caps is 5500 cm².

Answer 2

ANSWER

Sheet required will be on the curved surface area.

Curved surface area of 1 joker cap = πrl

Given,

• Radius, r = 7 cm

• Height, h = 24 cm

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