A container has 30 litres of water. If 3 litres of water is replaced by 3 litres of spirit and this operation is repeated twice, what will be the quantity of water in the new mixture?
A and B are two alloys of gold and copper prepared by mixing metals in the proportions 7 : 2 and 7 : 11 respectively. If equal quantities of the alloys are melted to form a third alloy C, proportion of gold and copper in C will be
To x litres of an x% solution of acid, y litres of water is added to get (x -10)% solution of acid. If x > 20, then value of y is
Two barrels contain a mixture of ethanol and gasoline. The content of the ethanol is 60% in the first barrel and 30% in the second barrel. In what ratio must the mixtures from the first and the second barrels be taken to form a mixture containing 50% ethanol ?
When one litre of water is added to a mixture of acid and water, the new mixture contains 20% acid. When one litre of acid is added to the new mixture, then the resulting mixture contains $33\frac{1}{3}$% acid. The percentage of acid in the original mixture was
To m litres of a m% solution of acid. x litres of water is muted to yield (m - 10)% solution of acid. If m > 25. then x equals
A man purchased 35 kg of rice at the rate of Rs.9.50 per kg and 30 kg at the rate of Rs.10.50 per kg. He mixed the two. Approximately, at what price (in Rupees) per kg. should he sell the mixture to make 35 per cent profit in the transaction?
