Nine friends have a dinner in a hotel. Eight of them spent $Rs.\, 12$ each on their meals and the ninth spent $Rs. \,16$ more than the average expenditure of all the nine. Find out the total money in $Rs.$ spent by them?

A man covers $\frac{1}{3}$ of his journey by train at $80\, km / h ,$ next $\frac{1}{3}$ by $60\, km / h$ and the rest by bicycle at $30 \,km / h$. Find the average speed of the man during the whole journey. (in $km/h$)

The average of $11$ numbers is $10.9$ If the average of the first six is $10.5$ and the average of last six is $11.4,$ find the middle (sixth) number.

The average marks of a group of $20$ students on a test is reduced by $4$ when the topper who scored $90$ marks is replaced of a new students. Find the marks of the new student.

The average speed of a train running at a speed of $30\, km / h$ during the first $100\, kilometres,$ at $40\, km / h$ during the second $100\, kilometres$ and at $50\,km / h$ during the last $100\, kilometres$ is nearly (in $km/h$)

The average of consecutive numbers is $n .$ If the next two consecutive numbers are also included, the average of the five numbers will