Three bottles of equal capacity have mixture of milk and water in ratio 5 : 7, 7 : 9 and 2 : 1 respectively. These three bottles are emptied into a large bottle. What is the percentage of milk in the new mixture?
Amar can complete a work in 30 days and Raman can complete the same work in 15 days. If both of them work together, then in 4 days what percent of the total work will be completed?