Question

There are 40 people standing in a row. A is 12th from the left and B is 9th from the right. How many people are there in between A and B?

• A. 18
• B. 19
• C. 20
• D. None of these

Hint:

When converting “from the right” to “from the left” in a row of \(N\): use \(N-\text{(from right)}+1\). Then subtract the two left-positions and minus one to count the people between.

Answer 1

The Correct Option is B

Total people \(=40\).
Position of A from the left \(=12\).
Position of B from the right \(=9\).
Step 1: Convert B’s position to “from the left.”
B’s position from the left \(= 40-9+1 = 32\).
Step 2: Count people strictly between positions 12 and 32.
Number between \(= 32-12-1 = 19\).
\(\boxed{19}\)