If "basis points" are defined so that $1 \%$ is equal to $100$ basis points,then by how many basis points is $82.5 \%$ greater than $62.5 \%$?

On decreasing the price of a colour $TV$ by $30 \%$,its sale is increased by $20 \%$. The effect on the revenue is:

The population of Delhi two years ago was $55000$. It increased by $12 \%$ in the first year and decreased by $15 \%$ in the second year. What was the population of the town at the end of $2$ years?

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?

$88 \%$ of $370 + 24 \%$ of $210 - ? = 118$

Two numbers are less than a third number by $30 \%$ and $37 \%$,respectively. How much per cent is the second number less than the first?