A certain school has $500$ students, $262$ of whom are boys. It has $50$ teachers, $20$ of whom are men. What is the percentage of females in the school?

Arshad's income is $20\%$ less than that of Rashid. How much per cent is Rashid's income more than Arshad's income?

Waida went to school for $225$ day in a full year. If her attendance is $75\%$, find the number of days the school opened.

A property dealer charges a commission of $3\%$ on first $₹20000$ and $2\%$ of the remaining selling price. Find his commission if a house is sold for $₹180000$.

The value of a machine depreciates every year by $5\%$. If its present value is $₹100000$. What will be its value after $2$ years?

The population of a town increase by $6\%$ annually. If its present population is $120000$. What will be its population after $2 years$. 

The population of a town increase by $6\%$ annually. If its present population is $120000$. What was its population a year ago?

Ankit was given an increment of $12\%$ on his salary. His new salary is $₹3864$. What was his salary before the increment?

A garden has $2000$ trees. $12\%$ of these are mango trees, $18\%$ are lemon and the rest orange trees. Find the number of orange trees.