We have asked to determine the height of telephone pole using the properties of similarities, if a 15 metres high tower casts a shadow of 24 metres long at a certain time and at the same time, a telephone pole casts a shadow 16 metres.
ML Aggarwal Avichal Publication class 10, chapter 13, question no 21
From the question it is given that,
Height of a tower PQ=15m
It’s shadow QR=24 m
Let us assume the height of a telephone pole MN=x
It’s shadow NO=16m
Given, at the same time,
△PQR∼△MNO
Therefore,
PQ/MN=ON/RQ
15/x=24/16
By cross multiplication we get,
x=(15×16)/24
x=240/24
x=10
Therefore, height of pole =10m.