the work done by a man, a woman and a child is in the ratio of 3: 2: 1. There are 20 men, 30 women and 36 children in a shoe factory. Their hourly wages amount to Rs. 780, which is divided in the ratio of work done by the men, women and children. What will be the wages of 15 men, 21 women and 30 children for 2 hours?