Along a road lie an odd number of stones placed at intervals of 10 metres. These stones have to be assembled around the middle stone. A person can carry only one stone at a time. A man carried the job with one of the end stones by carrying them in succession. In carrying all the stones he covered a distance of 3 km. Find the number of stones.

Explanation

Let say There are` 2n + 1 `stones in total


so there will be n stones each side of middle stone


Man started job from one end


so distance covered for 1st stone `= n * 10 m`


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