In an election between two candidates,one got $55 \%$ of the total valid votes,and $20 \%$ of the total votes were invalid. If the total number of votes polled was $7500$,what was the number of valid votes that the other candidate received?

If $8 \%$ of $x = 4 \%$ of $y,$ then $20 \%$ of $x$ is:

Rama's expenditure and savings are in the ratio $3:2$. His income increases by $10\%$. His expenditure also increases by $12\%$. His savings increases by: (in $\%$)

The number of students in a class is increased by $20 \%$ and the number now becomes $66$. Initially,the number was:

Two jars contain equal quantities of $40 \%$ alcohol. Swati changed the concentration of the first jar to $50 \%$ by adding extra quantity of pure alcohol. Sonali changed the concentration of the second jar to $50 \%$ by replacing a certain quantity of the solution with pure alcohol. By what percentage is the quantity of alcohol added by Swati more than that replaced by Sonali?

If the price of a book is first decreased by $25 \%$ and then increased by $20 \%,$ then the net change in the price will be