Question

The area of a circular field is 6.7914 hectares. Find the cost of

fencing it at the rate of Rs. 2.20 Per meter.

A - Rs. 20328

B - Rs. 10528

C - Rs. 20444

D - Rs. 24562​

Answer 1

Answer:

Area of circular field = 13.86 hectors.

1 hector = 10000 sq m

=> 13.86 hector = 138600 sq m

=> circumference = 924

=> cost of fencing 1 m = 20 paisa

cost of fencing 924 m =?

=> 924*2.2= 2032.8₹

Answer 2

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$\huge\tt{GIVEN:}$

• The area of a circular field is 6.7914 hectares

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$\huge\tt{TO~FIND:}$

• The cost of fencing it at the rate of Rs. 2.20 Per meter.

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$\huge\tt{SOLUTION:}$

⟹1 Hectare = 10000m².

⟹6.7914 hectares = 6.7914 × 10000 = 67914m²

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Then,

⟹Area of circular Field = 67914 m²

⟹ πr² = 67914

⟹ (22/7) ×r² = 6794

⟹ 22 × r² = 67914 ×7

⟹r² = 3087 × 7

⟹r² = 21 × 21 × 7 × 7

⟹ r² = (21)² × (7)²

⟹r = 21 ×7

⟹ r = 147 m.

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Now,

⟹ Circumference of circular Field = 2 π r

⟹ Circumference = 2 × (22/7) ×147

⟹ Circumference= 2 × 22 × 21

⟹ Circumference= 924m

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So,

⟹cost of fencing for 1m = Rs.2.20

⟹cost of fencing for 924m = 2.2 × 924 = ₹2032.8

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$\huge\tt{OPTION~A~IS~CORRECT}$

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