A pole 23 m long reaches a window which is 3\(\sqrt5\) m above the ground on one side of a street. Keeping its foot at the same point, the pole is turned to the other side of the street to reach a window 4\(\sqrt15\) m high. What is the width (in m) of the street?

A pole 23 m long reaches a window which is 3\(\sqrt5\) m above the ground on one side of a street. Keeping its foot at the same point, the pole is turned to the other side of the street to reach a window 4\(\sqrt15\) m high. What is the width (in m) of the street? Correct Answer 39

Given:

The length of the pole = 23 m

The first window is 3√5 m above the ground and the second window is 4√15 m above the ground.

Formula used:

In a right-angled triangle,

Base = √(Hypotenuse2 - Perpendicular2)

Calculation:

[ alt="F2 SSC Pranali 13-6-22 Vikash kumar D3 " src="//storage.googleapis.com/tb-img/production/22/06/F2_SSC_Pranali_13-6-22_Vikash%20kumar_D3_.png" style="width: 284px; height: 172px;">

Here, the width of the street = BC

In ΔABO, BO = √(AO2 - AB2)

= √(232 - 3√52)

= √(529 - 45)

= √484 = 22 m

In ΔOCD. CO = √(DO2 - DC2)

= √(232 - 4√152)

= √(529 - 240)

= √289 = 17 m

Then, BC = BO + CO = 22 + 17 = 39 m

∴ The width (in m) of the street is 39 m

Related Questions

How far is point 'R' from Point 'T'? Statement (I): Point 'R' is 5 metres to the north of point 'M'. Point 'U' is 4 metres to the east of point 'R'. Point 'T' is to the west of point 'R' such that points 'U' 'R' and 'T' form a straight line of  metres. Statement (II): Point 'Z' is metres to the south of point 'T'. Point 'U' is  metres to the east of point 'T'. Point 'M' is  metres to the east of point 'Z'. Point 'R' is  metres to the north of point 'M'. Point 'R' lies on the line formed by joining points 'T' and 'U'.