In a bag, the number of ₹5 coins is 8 more than the number of ₹10 coins but 20% less than the number of ₹2 coins. If total amount in the bag is ₹270, what is the number of ₹5 coins?

A vendor sells potatoes at a cost price, but he mixes some rotten potatoes and thereby gains 25%. The percentage of rotten potatoes in the mixture is? 

In 64 liter of pure alcohol, 20 liter of water is mixed and then $$ {1\over 4}{th}$$ of the mixture is taken out. When x liter of water is added again then ratio of water to that of the alcohol becomes 1:2. Find value of x?

A drink of chocolate and milk contains 8% pure chocolate by volume. If 10 litres of pure milk are added to 50 litres of this drink, the percentage of chocolate in the new drink is:

Rajesh purchased two different kinds of alcohol. In the first mixture, the ratio of alcohol to water is 4 : 5 and in second mixture it is 6 : 7. If he mixes the two given mixtures and makes a third mixture of 22 litres in which the ratio of alcohol to water is 5 : 6, the quantity of first mixture that is required to make 22 litres of the third kind of mixture is.

How many grams of water should be mixed in 9 grams of shaving lotion having 50% alcohol content so that the alcohol content in the lotion becomes 30%?

A mixture contains wine and water in a ratio of 5: 1. On adding 5 litres of water, the ratio of wine to water becomes 5: 2. The quantity of wine in the mixture is?

50 grams of an alloy of gold and silver contains 80% gold by weight, how much more gold should be mixed in this metal so that the alloy contains 95% gold?