if 10 litres of an oil of rs . 50 per litres be mixed with 5 litres of another oil of rs . 68 per litre then what is the rate of mixed oil per litre ?
"50 * 10 = 500 68 * 5 = 340 840 / 15 = 56 answer : c"
divide(add(multiply(10, 50), multiply(5, 68)), add(10, 5))