Letter positions from both ends: A letter is 5th from the left and 12th from the right in a row. How many letters are in the row?

Introduction / Context:
When the same object's position is given from both ends in a single row, the total count equals the sum of the two positions minus 1.

Given Data / Assumptions:

• Left-position = 5.
• Right-position = 12.

Concept / Approach:
Use N = left + right − 1.

Step-by-Step Solution:

Verification / Alternative check:
Converting right to left via N − left + 1 should return 12 for N = 16: 16 − 5 + 1 = 12, consistent.

Why Other Options Are Wrong:

• 15, 17, 18: Typical arithmetic slips around the −1 rule.
• None of these: Correct answer listed.

Common Pitfalls:
Adding positions without subtracting 1.

Final Answer:
16