In the last financial year,a car company sold $41,800$ cars. In this year,the target is to sell $51,300$ cars. By what percent must the sale be increased?

An empty fuel tank of a car was filled with an ordinary type of petrol. When the tank was one-third empty,it was filled with high-speed petrol. Again,when the tank was one-third empty,it was filled with an ordinary type of petrol. Again,when the tank was one-third empty,it was filled with high-speed petrol. At this time,what was the percentage of high-speed petrol in the tank?

Starting with $8000$ workers,the company increases the number of workers by $5 \%$,$10 \%$,and $20 \%$ at the end of the first,second,and third year,respectively. The number of workers in the fourth year is:

$A$ village lost $12 \%$ of its goats in a flood and $5 \%$ of the remainder died from diseases. If the number left now is $8360$,what was the original number before the flood?

$A$ student has to secure $15\%$ marks to pass the examination. If he gets $80$ marks and fails by $70$ marks,find the maximum marks set for the examination.

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