A man looks at the reflection of the top of the lamp-post on the mirror that is 6.6 m away from the foot of the lamppost. The man’s height is 1.25 m and he is standing 2 m away from the mirror. Assuming that the mirror is placed on the ground, facing the sky and the man, and that the mirror and the lamp-post are in a same line, find the height of the lamp-post (in metres).
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 4.13.
Given that, Distance of lamp-post from mirror = 6.6 m
Distance of man from the mirror = 2 m
Height of man = 1.25 m
Height of lamp-post/Distance of lamp-post from mirror = Height of man/Distance of man from mirror
According to the given question,
Let the height of the lamp-post be h meters.
⇒ h/6.6 = 1.25/2
⇒ h = 4.125 ≈ 4.13