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प्रश्न
The cost of levelling the ground in the form of a triangle having the sides 51 m, 37 m and 20 m at the rate of Rs 3 per m2 is Rs 918.
पर्याय
True
False
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उत्तर
This statement is True.
Explanation:
a = 51, b = 37, c = 20
`s = (a + b + c)/2`
⇒ `s = (51 + 37 + 20)/2 = 108/2 = 54`.
Area (Δ) = `sqrt(s(s - a)(s - b)(s - c))`
⇒ Area (Δ) = `sqrt(54(54 - 51)(54 - 37)(54 - 20))`
⇒ Area (Δ) = `sqrt(54 xx 3 xx 17 xx 34)`
⇒ Area (Δ) = 306 m2
Cost of painting = Area (Δ) × Cost per m2
⇒ Cost of painting = 306 × 3 = Rs. 918
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