Answer: Increase; 3%
Step-by-step explanation:
Price elasticity of demand measures the sensitivity of demand to a change in prices. When this measure is negative, it means that an increase in price, will result in a decrease in quantity demanded.
Formula is:
Price elasticity of demand = Change in Quantity demanded / Change in price
If the government wants to reduce consumption by 15%, the price increase should be:
-5 = -15% / p
-5p = -15%
p = -15%/-5
p = 3%