A TV’s price is reduced by 30% and sales increase by 20%. What is the overall percentage change in revenue (price × quantity)?

Introduction / Context: Revenue is the product of price and quantity sold. When both factors change, multiply the respective percentage multipliers to get the combined effect, and then translate back into a percentage change.

Given Data / Assumptions:

• Price change: −30% ⇒ multiplier 0.70.
• Quantity change: +20% ⇒ multiplier 1.20.
• Initial revenue serves as 100% reference.

Concept / Approach: New revenue factor = 0.70 * 1.20 = 0.84. That is 84% of the original, hence a 16% decrease overall.

Step-by-Step Solution:

Verification / Alternative check: If original price = ₹100 and sales = 100 units ⇒ revenue = ₹10,000. New price = ₹70; new sales = 120 units; new revenue = ₹8400 ⇒ 16% down.

Why Other Options Are Wrong: A 10% change comes from adding or subtracting percentages instead of multiplying; “16% increased” flips the sign.

Common Pitfalls: Adding −30% and +20% to get −10% (wrong). Effects on different factors must be multiplied.

Final Answer: 16% decrease