A boat travel 240 km downstream in 3 hours and the time is taken by the boat to travel the same distance in upstream in 6 hours. Find the speed of stream (in kmph).

The average age of Ram and his son is 48 years. The ratio of their ages 13 years ago was 11 : 3. What is the present age of son?

A vessel contain some litres of pure milk. If 25 litre of water is added to the vessel, then ratio between milk and water becomes 12:5, 17 litres of mixture is drawn from the vessel and 10 litre of water is added to the mixture. Find the new ratio between milk and water. 

A sum of ₹ 800 amounts to ₹ 920 in 3 years at the simple interest rate. If the rate is increased by 3 % p.a., what will be the sum amount to in the same period? 

A distance is covered by a cyclist at a certain speed. If a jogger covers half the distance in double the time, the ratio of the speed of the jogger to that of the cyclist is 

A certain number of men can do a work in 60 days. If there were eight more men, it could be completed in 10 days less. How many men were there in the beginning?

In a race of 200 metres, B can give a start of 10 metres to A and C can give a start of 20 metres to B. The start that C can give to A, in the same race, is