GIVEN:Selling price of each calculator = Rs. 560Profit % = 12%Formula USED:S.P = [(100 + P%)/100] × C.PCalculation:According to the question,560 = [(100 + 12)/100] × C.P⇒ C.P = (560 × 100)/112⇒ C.P = Rs. 500Profit on each watch = 560 - 500⇒ Profit on each watch = 60Profit on 8 calculator per day = 60 × 8⇒ Profit on 8 calculator per day in 15 days = 60 × 8 × 15⇒ Profit on 8 calculator per day in 15 days = Rs. 7200∴ The TOTAL profit earned in 15 days is Rs. 7200.