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प्रश्न
A boy 1.7 m tall is standing on a horizontal ground, 50 m away from a building. The angle of elevation of the top of the building from his eye is 60°. Calculate the height of the building. (Take `sqrt(3)` = 1.73)
उत्तर
Let PR be the building and AB be the boy
In ∆PQR, tan 60° = `(PQ)/50` ⇒ PQ = `50sqrt(3)` m
Height of the building = PR = `(50sqrt(3) + 1.7)` m = 88.2 m
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