In a row of 60 students, P is 18th from the left and Q is 25th from the right. How many students are between P and Q?

The correct answer is 17.

Step-by-step explanation:

Step 1: Understand the given information
Total number of students in the row = 60
Position of P from the left end = 18th
Position of Q from the right end = 25th

Step 2: Check for overlap
To determine if P and Q cross each other in the row, we find the sum of their positions from both ends:

$\text{Sum of positions}=18+25=43$
Since the sum of their positions (43) is less than the total number of students (60), P and Q do not overlap. There is a space between P and Q in the middle of the row.

Step 3: Calculate the number of students between P and Q
For a non-overlapping scenario, the number of students sitting between two individuals is calculated using the formula:
Number of students between P and Q = Total students - (Position of P from left + Position of Q from right)

Substituting the values into the formula:

$\text{Number of students between P and Q}=60-(18+25)$

$\text{Number of students between P and Q}=60-43$

$\text{Number of students between P and Q}=17$

Therefore, there are 17 students sitting between P and Q.