Salman, Ambani, and Dalmiya together have an average of 60 shirts. If each buys 6 more shirts, what is the new average number of shirts per person?

Introduction / Context:
When each member of a group adds the same quantity, the group average increases by that quantity as well. This property saves time over recomputing totals from scratch.

Given Data / Assumptions:

• Initial average shirts per person = 60
• Three people
• Each buys 6 more shirts

Concept / Approach:
If everyone adds the same number x, the average increases by x. No need to know individual counts to find the new mean.

Step-by-Step Solution:

Verification / Alternative check:
Total initially = 60 * 3 = 180. Added total = 6 * 3 = 18. New total = 198. New average = 198 / 3 = 66. Confirms the shortcut.

Why Other Options Are Wrong:

• 63 and 62: Do not reflect the full +6 change per person.
• can't be determined: The rule permits determination without individual breakdowns.
• None of these: A correct exact value exists (66).

Common Pitfalls:
Adding 6 only once to the total instead of per person, which would understate the increase in the mean.

Final Answer:
66