A dishonest delivery man purchases 20 liters of pure milk and dilutes it by adding 4 liters of water. If he sells the diluted milk at Rs.50/L, then what is the cost price of pure milk?

Pipes A and B can fill a tank in 5 hours and 6 hours respectively. Another Pipe can empty the full tank in 30 hours. If all three pipes are opened together, then the tank will be filled in :

A retailer has 250 kg of rice a part of which he sells at 10% profit. The remaining quantity of rice is of low quality and he sold it at 5% loss. Overall he made a profit of 7%. The quantity of rice sold at 5% loss is :

In a kilometer race, A can beat B by 100 m. In a race of 400 m, B can beat C by 40 m. By how many meters will A beat C in a race of 500 m?

A motor boat goes 20 km downstream and comes back to the starting point in 6 hours. If the speed of the boat in still water is 12 km/h, then the speed of the stream is :

A boat takes 6 hr 25 minutes to row upstream a certain distance with a speed which is 14.4 times that of the river current. The time taken by the boat to row down the same distance with same speed is:

The cost of type A cement is Rs 100 per kg and that of type B cement is Rs 120 per kg. If both are mixed in the ratio of 2:3, the price of the cement mixer per kg will be