A flag pole 18 m high casts a shadow 9.6 m long. Find the distance of the top of the pole from the far end of the shadow.
Let MN = 18 m be the flag pole and its shadow be LM = 9.6 m.
The distance of the top of the pole, N from the far end, L of the shadow is LN.
In right angled ∆LMN,
LN2 = LM2 + MN2 [by Pythagoras theorem]
⇒ LN2 = (9.6)2 + (18)2
⇒ LN2 = 9.216 + 324
⇒ LN2 = 416.16
∴ LN = √416.16 = 20.4 m
Hence, the required distance is 20.4 m
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