Self-referential average spending: Nine friends dine together. Eight spend ₹12 each. The ninth spends ₹16 more than the average expenditure of all nine. Find the total money spent.

Introduction / Context:
This problem defines one person’s spend in terms of the unknown overall average, producing an equation in that average. Solve for the average first, then get the total and check consistency.

Given Data / Assumptions:

• Eight people: ₹12 each
• Ninth person: average of all nine + ₹16

Concept / Approach:
Let the average be x. Then total = 9x. Known spend = 8 * 12 + (x + 16). Set equal to 9x and solve for x, then multiply back to get the total amount.

Step-by-Step Solution:

Verification / Alternative check:
Ninth person’s spend = x + 16 = 14 + 16 = ₹30; eight others = ₹96; total = ₹126. Average 126/9 = 14 matches x.

Why Other Options Are Wrong:

• ₹135, ₹111, ₹141, ₹129: do not equal 9 * 14 under the self-referential condition.

Common Pitfalls:
Assuming the ninth spent ₹16 more than the others rather than more than the average, which changes the equation structure.

Final Answer:
₹ 126