Given:Consumption of antacid in a week = 32 tablets Calculation: Consumption of antacid in a year = 32 × 52 weeks = 1664 tablets Yearly expenditure based on current price = 1664 × 1.5 /10 = Rs.249.6Yearly expenditure based on revised price = 1664 × 2.5/10 = Rs.416? The required percentage = 416 - 249.6/249.6 × 100 = \(66 \frac{2}{3}\)%Alternate MethodIncreased price per tablet = 2.5 - 1.5 = 1Required percentage = (2.5 - 1.5)/1.5 × 100 = \(66 \frac{2}{3}\)%An increase in price percentage will be the same for 1 tablet or 10 tablets or tablets required for a year as long as the initial price and revised price are the same for every 10 tablets or 1 tablet.