The average of marks obtained by $120$ candidates was $35.$ If the average of marks of passed candidates was $39$ and that of failed candidates was $15,$ the number of candidates who passed the examination is

If the average of $m$ numbers is $n^{2}$ and that of $n$ numbers is $m^{2},$ then the average of $( m + n )$ numbers is

Fifteen movie theatres average $600$ customers per theatre per day. If $six$ of the theaters close down but the total theater attendance stays the same, then the average daily attendance per theatre among the remaining theaters is

The average monthly salary of all the employees in an industry is $Rs.\, 12,000$. The average salary of male employees is $Rs.\,15,000$ and that of female employees is $Rs.\, 8,000 .$ What is the ratio of male employees to female employees?

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

A cricketer whose bowling average is $12.4$ runs per wicket takes $5$ wickets for $26$ runs and thereby decreases his average by $0.4$ The number of wickets taken by him till the last match was