When a number is increased by $216$,it becomes $140\%$ of itself. What is the number?

Which number is $60 \%$ less than $80$?

Two numbers are more than the third number by $20 \%$ and $80 \%$ respectively. The first number is what percent of the second number?

The price of a shirt is increased by $15 \%$ and then reduced by $15 \%$. The final price of the shirt

An ore contains $23 \%$ copper. To get $69 \text{ kg}$ of copper, the quantity of the ore required is: (in $\text{ kg}$)

Mr. Katial buys a house for ₹$100000$ and rents it out. He puts $12.5 \%$ of each month's rent aside for upkeep and repairs,pays ₹$325$ per year as taxes,and realizes a $5.5 \%$ annual return on his investment. Find the monthly rent.