A man 1.8 m tall stands at a distance of 3.6 m from a lamp post and casts a shadow of 5.4 m on the ground. Find the height of the lamp post.
Heights & Distances
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Question

A man 1.8 m tall stands at a distance of 3.6 m from a lamp post and casts a shadow of 5.4 m on the ground. Find the height of the lamp post.

KnowledgeBoat · Accepted Answer

Given, AB is the lamp post and CD is the height of man and CE is the shadow of the man. CE || DB. Take AB = x and CD = 1.8 m FA = CD = 1.8 m DF = CA = 3.6 m BF = AB - FA = (x - 1.8) m Shadow (EC) = 5.4 m Considering right angled △BDF, we get : Considering right angled △DCE, we get : Comparing Eq 1 and Eq 2 we get, Hence, the height of the lamp post is 3 meters.

Mathematics

A man 1.8 m tall stands at a distance of 3.6 m from a lamp post and casts a shadow of 5.4 m on the ground. Find the height of the lamp post.

Heights & Distances

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