Along a road lie an odd number of stones placed at the interval of 10m. These stones have to be assembled around the middle stone.

Question

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

Answer 1

Solution: Let the total number of stones be 2n + 1, i.e., there are n stones to the left of middle stone and n to its right.

Since the man starts from one point, total distance travelled by him for collecting all stone to the middle stone is:

Therefore, number of stones = 2n + 1 = 2(12) + 1 = 25