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 the left. How many boys are there in the row ?
A. 27
B. 31
C. 23
D. 28
Answer:C
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 the left. How many boys are there in the row ?
A. 27 B. 31 C. 23 D. 28