Question

A kid is standing 4 m away from a pole of height 7m and another pole is 8 m behind it. If the kid’s vision is 1 m from the ground, find the height of the second pole. (Assuming both poles are perpendicular to the ground)

• A. 18
• B. 19
• C. 20
• D. 21

Answer 1

The correct option is B 19

Consider $\Delta APQ$ and $\Delta ABC,$

$\angle PAQ=\angle CAB$ (common angle)
APQ = ABC (right angle)

$\Delta APQ\sim \Delta ABC$ (by AA criteria)
$\therefore \frac{AP}{AB}=\frac{PQ}{BC}\Rightarrow \frac{4}{12}=\frac{6}{BC}$
$BC=18m$
Length of the pole = BC + 1 m = 19 m