Of the three numbers whose average is $60$,the first is one-fourth of the sum of the others. The first number is

The bowling average of a cricketer was $12.4$. He improves his bowling average by $0.2$ points when he takes $5$ wickets for $26$ runs in his last match. The number of wickets taken by him before the last match was?

The average weight of $4$ men $A, B, C,$ and $D$ is $67 \, kg.$ When a $5^{th}$ man $E$ is included,the average weight decreases by $2 \, kg.$ $A$ is replaced by $F.$ The weight of $F$ is $4 \, kg$ more than $E.$ The average weight decreases because of the replacement of $A,$ and now the average weight is $64 \, kg.$ Find the weight of $A.$

The average of the first nine prime numbers is:

Of three numbers,the second is thrice the first and the third number is three-fourths of the first. If the average of the three numbers is $114$,the largest number is

$A$ 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?