Commission scaling with hours and rate: A marketing manager earns ₹240 for a 40-hour week. In the final week, the rate increases by 50% and he works 60 hours. What commission does he earn that week?

Introduction / Context:
This item connects hourly pay rate, hours worked, and proportional changes. A percentage increase in rate multiplies the base hourly rate while hours scale total earnings linearly.

Given Data / Assumptions:

• Earnings at base = ₹240 for 40 hours ⇒ base rate = ₹240/40 = ₹6 per hour.
• Rate increases by 50% ⇒ new rate = 1.5 * 6 = ₹9 per hour.
• Final week hours = 60 hours.

Concept / Approach:
Total commission = (hourly rate) * (hours). Apply the rate hike first, then multiply by the longer work duration to get the final week’s commission.

Step-by-Step Solution:
Base rate = 240 / 40 = ₹6/hNew rate after 50% increase = 6 * 1.5 = ₹9/hCommission = 9 * 60 = ₹540

Verification / Alternative check:
Relative scaling: earnings scale by both rate and time. Compared to base, factor = 1.5 (rate) * (60/40) = 1.5 * 1.5 = 2.25. Base week ₹240 * 2.25 = ₹540. Same result.

Why Other Options Are Wrong:
500, 520, 600, 480 do not match the exact multiplication of rate and hours given by the scenario.

Common Pitfalls:
Adding 50% of weekly earnings and then scaling hours, instead of adjusting the hourly rate first and then multiplying by hours.

Final Answer:
540