Q37 of 40 Page 1

As observed from the top of a 75m high light house above the sea level, the angles of depression of two ships are 30° and 45° respectively. If one ship is exactly behind the other on the same side of the light house and in the same straight line, find the distance between the two ships. (use √3 = 1.732)


Let CD = x m, AB = 75 m


In Δ ACB,



⇒ BC = AB = 75 m


In Δ ADB,




⇒ BD = 75√3


⇒ BC + x = 75√3


⇒ 75 + x = 75√3


⇒ x = 75(√3 – 1) = 54.9 m


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