In a row of boys, if A who is 10th from the left and B who is 9th from the right interchange their positions, A becomes 15th from left. How many boys are there in the row?
Correct Answer: 23
Explanation:
According to question B is 9th from the right end and A is 15th from the left end.
Therefore, Total number of boys in the row = B's position in row + A's position in row - 1
Total number of boys in the row = 9 + 15 – 1 = 23
