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A man goes 18 m due east and then 24 m due north. Find the distance of his current position from the starting point?

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#### Solution

Let the initial position of the man be “O” and his final position be “B”.

By Pythagoras theorem

In the right ∆OAB,

OB^{2} = OA^{2} + AB^{2}

= 18^{2} + 24^{2}

= 324 + 576 = 900

OB = `sqrt(900)` = 30

The distance of his current position is 30 m

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