The average of $25$ consecutive odd integers is $55 .$ The highest of these integers is

The average height of the students of a class of $20$ is $105\, cm$. If ten more students of average height of $120 \,cm$ join this class, the average height of the class will become (in $cm$)

The average revenue of $13$ consecutive years of a company $Rs.\, 70$ $\,lakhs.$ If the average of first $7 \,years$ is $Rs.\, 65$ $\,lakhs$ and that of last $7\, years$ is $Rs.\, 77$ $\,akhs,$ find the revenue for the $7^{th}$ $year.$ (Rs. in $lakh$)

Find the average of all the numbers between $6$ and $34$ which are divisible by $5$

A batch of $60$ students made an average score of $50$ marks and another batch of $40$ students made it only $45 .$ What is the overall average score ?

A student finds the average of ten $2 -$digit numbers. While copying numbers, by mistake, he writes one number with its digits interchaged. As a result his answer is $1.8$ less than the correct answer. The diference of the digits of the number, in which he made mistake, is