Ranking test – swap and deduce total: In a row of girls, Kamya is 5th from the left and Preeti is 6th from the right. When they exchange positions, Kamya becomes 13th from the left. What is Preeti's position from the right after the exchange?

Introduction / Context:
Swapping people in fixed seats preserves the seats’ absolute indices. A post-swap rank lets us deduce total N, then convert to the requested rank.

Given Data / Assumptions:

• Before swap: Kamya = 5th from left; Preeti = 6th from right.
• After swap: Kamya = 13th from left (so she sits in Preeti’s former seat).

Concept / Approach:
Preeti’s original seat is 13th from left and also 6th from right. Thus N − 13 + 1 = 6, giving N. After swap, Preeti moves to Kamya’s former seat (5th from left), so we convert to right-rank.

Step-by-Step Solution:

Verification / Alternative check:
Check consistency: a seat 13th from left is indeed 6th from right when N = 18 (since 18 − 13 + 1 = 6).

Why Other Options Are Wrong:
7th/11th/18th correspond to incorrect N or to converting the wrong seat.

Common Pitfalls:
Using persons’ ranks post-swap as if they were seat indices pre-swap; forgetting the +1 term in conversions.

Final Answer:
14th