The average of runs scored by a cricketer in his $99$ innings is $99.$ How many runs will he have to score in his $100^{\text {th }}$ innings so that his average of runs in $100$ innings may be $100 ?$

The average of $25$ results is $20 .$ the average of first $12$ results is $15$ and that of the last $12$ results is $18 .$ Then, the $13^{ th}$ results is

Out of seven given numbers, the average of the first four numbers is $4$ and that of the last four numbers is also $4 .$ If the average of all the seven numbers is $3,$ then fourth number is?

The average price of $80$ computers in an electronic shop is $Rs.\, 30,000 .$ If the highest and lowest price computers are sold out then the average price of the remaining $78$ computers is $Rs.\, 29,500 .$ The cost of the highest price computer is $Rs.\, 80,000 .$ The cost of lowest price computer is in $Rs.$ 

Last year, $5$ companies had an average of $16$ non working days each, and $2$ companies had $5$ fewer non working days each. What was the average number of non working days given by the same companies this $year$ ?

The sum of five consecutive integers is $a$ and the sum of next five consecutive integers is $b$. Then $\frac{(b-a)}{100}$ is equal to