The average of $5$ quantities is $6 .$ The average of three of them is $8 .$ What is the average of remaining two quantities?
$2$
$5$
$9$
$7$
Of the three numbers, second is twice the first and is also thrice the third. If the average of the three numbers is $44,$ the largest number is
The average of first three numbers is double of the fourth number. If the average of all the four numbers is $12,$ find the $4^{th}$ number.
The average weight of $3$ men $A, B$ and $C$ is $84 \,k g .$ Another man, $D,$ joins the group, and the average weight becomes $80\, kg .$ If another man, $E$, whose weight is $3 \,kg$ more than that of $D ,$ replaces $A$, then average weight of $B , C , D$ and $E$ becomes $79 \,kg$. The weight of $A$ is (in $kg$)
The average of $30$ numbers is $15 .$ The average of the first $18$ numbers is $10$ and that of the next $11$ numbers is $20 .$ The last number is
The average age of four brothers is $12 \,year.$ If the age of their mother be also included, the average is increased by $5\, year.$ The age of the mother (in $years$) is