Price Elasticity and Total Expenditure Steps:

• Price elasticity of demand (PED) = %ΔQ / %ΔP = -0.6.
• %ΔP = -50%, so %ΔQ = PED × %ΔP = -0.6 × (-50%) = +30%.
• Demand is inelastic (|PED| < 1), so price decrease raises quantity but lowers total expenditure (TR = P × Q).
• %ΔTR ≈ %ΔP + %ΔQ = -50% + 30% = -20% (falls).

Why B is correct:

• Matches calculation: quantity rises 30% from inelastic response; expenditure falls per inelastic demand rule (price cut reduces revenue when |PED| < 1).

Why the others are wrong:

• A: Quantity rises (not falls) with price decrease.
• C: Expenditure falls (not rises); quantity change is 30% (not 60%).
• D: Quantity rises (not falls); expenditure falls (not rises).

Final answer: B