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 $cm$)

$10\, kg$ of rice priced at $Rs. \,12$ per $kg$ is mixed with $6\, kg$ of rice priced at $Rs. \,16$ per $kg$. Find the average price in $Rs.$ per $kg$ of the whole mixture?

Average of $a, b$ and $c$ is $11 ;$ average of $c, d$ and $e$ is $17 ;$ average of $e$ and $f$ is $22$ and average of $e$ and $c$ is $17 .$ Find out the average of $a, b,$ $c , d , e$ and $f ?$

The average salary of all the associates in a team is $Rs.\,16000.$ The average salary of $7$ senior associates is $Rs.\,24000$ and the average salary of the rest is $Rs.\, 12000$. How many associates work in that team?

The average age of $36$ $students$ in a group is $14\, years.$ When teacher's age is included to it, the average increases by one what is the teacher's age in $years$ ?

If the average of $6$ consecutive even numbers is $25 ,$ the difference between the largest and the smallest number is