Three years ago,the average age of a family of $5$ members was $27 \text{ years}$. After the addition of a child to the family,the present average age of the family is still $27 \text{ years}$. Find the present age of the child (in years).

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 $Runs$):

Of the three numbers,the first is twice the second and the second is thrice the third. If the average of the three numbers is $10$,the numbers are

In a family,the average age of a father and a mother is $35 \text{ years}$. The average age of the father,mother,and their only son is $27 \text{ years}$. What is the age of the son (in $\text{years}$)?

Ashish has earned an average of $4200$ dollars for the first eleven months of the year. If he justifies his staying on in the $US$ on the basis of his ability to earn at least $5000$ dollars per month for the entire year,how much should he earn (in dollars) in the last month to achieve his required average for the whole year?

The average of the squares of the first ten natural numbers is