In a row of boys P is 28th from the left and Q is 17th from the right. They interchange their positions with each other and P become 42nd from the left. What is the position of Q from the right when he interchanged his position with P?
Answer & explanation
Correct answer: option 3
First of all, we have to find the total number of boys in the row,
Step 1:
T = L + R - 1
= 42 + 17 – 1
⇒ 58
Step 2: Now position of Q from the right is,
R = T – L + 1
= 58 – 28 + 1
⇒ 31