A person was standing on a road near a mall, He was 1425 m away from the mall and able to see the top of the mall from the road in such a way that the top of a tree, which is in between him and the mall, was exactly in the line of sight with the top of the mall. The tree height is 10 m and it's 30 m away from him. How tall ( in m ) is the mall?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 475
The person is 1425 m away from the mall. The height of the tree is 10 m and it is 30 m away from him.
tanθ = height/base
Let, the height of the mall (AB) = x m
From the figure -
CD = 10 m
DM = 30 m
BM = 1425 m
Let, ∠AMB = ∠CMD = θ
From ΔAMB and ΔCMD get -
AB/BM = CD/DM
x/1425 = 10/30
x/1425 = 1/3
x = 475