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A wire is bent into the form of a circle, whose area is 154 cm². If the same wire is bent into the form of an equilateral triangle, the approximate area of the equilateral triangle is
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- 93.14 cm²
- 90.14 cm²
- 83.14 cm²
- 39.14 cm²
- 93.14 cm²
Correct Option: A
Using Rule 14,
If the radius of circle be r cm, then
πr² = 154
| ⇒ | r² = 154 | |
| 7 |
| ⇒ r² = | 7 × 7 | |
| 22 |
∴r = 7 cm
∴ Length of wire = 2πr
| = 2 × | 7 × = 44 cm | |
| 7 |
Perimeter of equilateral triangle
| ∴ Side of equilateral triangle = | cm | |
| 3 |
| ∴ Area of equilateral triangle = | × side² | |
| 4 |
| ∴ Area of equilateral triangle = | × | × | |||
| 4 | 3 | 3 |
| = | = | ||
| 9 | 9 |
≈ 93.14 sq.cm.
