The average weight of $45$ students in a class is $52\, kg.$ Five of them whose average weight is $48 \,kg$ leave the class and other $5\, students$ whose average weight is $54\, kg$ join the class. What is the new average weight (in $kg$ ) of the class 

Sum of eight consecutive numbers of Set $A$ is $376$ What is the sum of $5$ consecutive numbers of another set if its minimum number is $15$ ahead of average of Set $A ?$

A number, $x,$ equals $80 \%$ of the average of $5,7,$ $14$ and a number $y$. If the average of $x$ and $y$ is $26$ then value of $y$ is

The mean of $50$ observations was $36 .$ It was found later that an observation $48$ was wrongly taken as $23 .$ The corrected new mean is

A man covers $\frac{1}{3}$ of his journey by train at $80\, km / h ,$ next $\frac{1}{3}$ by $60\, km / h$ and the rest by bicycle at $30 \,km / h$. Find the average speed of the man during the whole journey. (in $km/h$)