$A$ $20 \%$ raise of price followed by a discount of $25 \%$ on the raised price will:

The price of an article is Rs. $100$. Its price is increased by $10 \%$,and then again its price is increased by $10 \%$. What is the total increase in the price?

Evaluate $28 \%$ of $450 + 45 \%$ of $280$.

$A$ man wills $40 \%$ of his wealth to his wife and the rest to his children. What percentage of the wealth willed to the wife do the children get?

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:

In an examination,there are three papers and a candidate has to get $35 \%$ of the total to pass. In one paper,he gets $62$ out of $150$ and in the second $35$ out of $150$. How much must he get,out of $180$,in the third paper to just qualify for a pass?