a man goes 40 km north, then he goes 4o km east, then he goes 40 km southy and reaches the orignal place.... prove it

Answer :

Given : a man goes 40 km north, then he goes 4o km east, then he goes 40 km south.
So we show his path on diagram , As :

Now

DA  =  BC =  40 km ,

So he have to go 40 km West to reach his original place .  ( Ans )

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