SSC CGL 2022 PYQ — Question 69

The correct answer is option 4 i.e.  $\frac{100}{3}$(3 -√3)

Distance of man from the building = 50 m

The angle of elevation of the top of the poster = 45⁰

The angle of elevation of the bottom of the poster = 30⁰

tan θ = x/y (where x and y are perpendicular and the base of the right-angled triangle)

In triangle BCD, tan30⁰ = BC/CD

tan30⁰ = 1/√3

CD = 50m

BC/50 = 1/√3

BC = 50√3/3

In triangle ACD, tan45⁰ = AC/CD

AC = AB + BC

tan 45⁰ = 1 and CD = 50 m

AC = CD or AB + BC = CD

Substituting the values, we get -

AB + 50√3/3 = 50

AB = 50(3 - √3)/3

200% of the poster height = 100(3 - √3)/3ath widget