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 $km/h$)

A batsman has a certain average of runs for $12$ innings. In the $13^{th}$ innings, he scores $96$ runs and thereby increasing his average by $5$ runs. What is his average after the $13^{th}$ innings ?

Eleven years earlier the average age of a family of $4$ members was $28 \,years.$ Now the age of the same family with six members js yet the same, even when $2$ children were born in this period. If they belong to the same parents and the age of the first child at the time of the birth of the younger child was same as there were total family members just after the birth of the youngest member of this family, then the present age of the youngest member of the family is in $year$?

If the difference between the average of $x, y$ and $y$, $z$ is $12,$ then the difference between $x$ and $z$ is

Refer to the line graph and answer the giten question.

Number of candidates who qualified in a given competitite examination from $6$ states during two given $years$

What is the average number of candidates who qualified in the given competitive exam from states $Q,$ $S , T$ and $U$ in $2004 ?$