A can complete a work in 20 days and B can complete the same work in 25 days. If both of them work together, then in 3 days what percent of the total work will be completed?
A can do a piece of work in 10 days, B can do it in 12 days and C can do it in 15 days. In how many days will A, B and C finish it, working all together?
In a class of 56 students there are 28 girls. The average weight of these girls is 46 kg and average weight of the full class is 51 kgs. What is the average weight of the boys of the class?
A certain sum of money becomes 4 times of itself in 30 years at a rate of simple interest. In how many years it will become double of itself at the same rate of simple interest?