Arihant Expert Team Solutions for Exercise 1: Practice Exercise

$400$ students took a mock exam in Delhi. $60\%$ of the boys and $80\%$ of the girls cleared the cut off in the examination. If the total percentage of students qualifying is $65\%$, how many girls appeared in the examination?

A cistern contains $50 L$ of water. $5 L$ of water is taken out of it and replaced by wine. The process in repeated. Find the proportion of wine and water in the resulting mixture.

A dishonest grocer professes to sell pure butter at cost price, but he mixes it with adulterated fat and thereby gain $25\%$. Find the percentage of adulterated fat in the mixture assuming that adulterated fat is freely available.

$A$ and $B$ are two alloys of gold and copper in the ratio $7: 2$ and $7:11$ respectively. If equal quantities of these two alloys arc melted to form a new alloy $C$, then the ratio of gold and copper in $C$ is:

$A$ can contain a mixture of two liquids $A$ and $B$ in the ratio $7: 5$. When $9 L$ of mixture is drain off and the can is filled with $B$, the ratio of $A$ and $B$ becomes $7: 9$. How many litres of liquid $A$ was contained by the can initially?

Two vessels $\mathrm{A}$ and $\mathrm{B}$ contain milk and water mixed in the ratio $8:5$ and $5:2$, respectively. The ratio in which these two mixtures be mixed to get a new mixture containing $69\frac{3}{13}\%$ milk is

A mixture of milk and water is such that the quantity $3$ of milk is $5$ that of water. The proportion of milk in the mixture is:

Acid and water are mixed in a vessel $A$ in the ratio of $5 : 2$ and in the vessel B in the ratio of $8 : 5$. In what proportion should quantities be taken out from the two vessels so as to form a mixture in which the acid and water will be in the ratio of $9 : 4$?