In what ratio must sugar at ₹12 per kg be mixed with sugar at ₹20 per kg so that the mixture is worth ₹15 per kg?

If $x\%$ of $y + y\%$ of $30 = 61\%$ of $xy$, then $x =$

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

A vessel contains 56 litres of mixture of milk and water in the ratio 5:2. How much water should be mixed with it so that the milk to water ratio becomes 4:5

Pipes A and B can fill a tank in 20 hours and 30 hours respectively and pipe C can empty the full tank in 40 hours. If all the pipes are opened together, how much time will be needed to make the tank full ?

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?

In a 1000 m race P beats Q by 100 m and in the same race Q beats R by 200 m. By what distance does P beat R?