harkamal purchased 8 kg of grapes at the rate of 70 per kg and 9 kg of mangoes at the rate of 50 per kg . how much amount did he pay to the shopkeeper ?
"cost of 8 kg grapes = 70 × 8 = 560 . cost of 9 kg of mangoes = 50 × 9 = 450 . total cost he has to pay = 560 + 450 = 1010 . b )"
add(multiply(8, 70), multiply(9, 50))