The average weight of five persons sitting in a boat is $38\, kg$. The average weight of the boat and the persons sitting in the boat is $52\, kg$. What is the weight of the boat (in $kg$)?

The batting average of a cricket player for $64$ innings is $62$ runs. His highest score exceeds his lowest score by $180$ runs. Excluding these two innings,the average of the remaining innings becomes $60$ runs. His highest score was (in $Runs$):

$A$ class has $20$ boys and $30$ girls. The average age of boys is $11$ years and that of girls is $12$ years. What is the average age of the whole class in years?

The average age of a group of persons going for a picnic is $16.75 \text{ years}$. $20$ new persons with an average age of $13.25 \text{ years}$ join the group on the spot,due to which the average age of the group becomes $15 \text{ years}$. Find the number of persons initially going for the picnic.

The average weight of $15$ oarsmen in a boat is increased by $1.6\, kg$ when one of the crew,who weighs $42\, kg$,is replaced by a new man. Find the weight of the new man (in $kg$).

The average of $50$ numbers is $38$. If two numbers,namely $45$ and $55$,are discarded,the average of the remaining numbers is