The average of $12$ results is $15,$ and the average of the first two is $14.$ What is the average of the rest?

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 $year$?

The average age of $30$ girls is $1\, year.$ The average of first $18$ girls is $15\, year.$ Find out the average age of remaining $12$ girls?

The average age of Sachin and Ganguli is $35 \,years.$ If Kaif replaces Sachin, the average age becomes $32 \,years$ and if Kaif replaces Ganguli, then the average age becomes $38 \,years.$ If the average age of Dhoni and Irfan be half of the average age of Sachin, Ganguli and Kaif, then the average age of all the five people is:

Three year ago, the average age of a family of five members was $27 \,year.$ The present average age is also $27 \,year$ after the inclusion of a child into the family. Find the age of the child in $year$ ?

In a class, there are $20$ boys whose average age is decreased by $2$ $months,$ when one boy aged $18\, years$ in replaced by a new boy. The age of the new boy is