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 $km/h$)

The average pocket-money of $3$ friends $A, B, C$ is $Rs.\, 80$ $month.$ If $B$ spends double and $C$ spends triple of whate $A$ spends during that month and if the average of their unspent pocketemoney is $Rs.$ $60,$ then $A$ spends (in $Rs.$)

The average weight of a class of $24$ students is $35 \,kg$. If the weight of the teacher is included the average rises by $400\, g.$ The weight of the teacher is (in $kg$)

The average monthly expenditure of a family for the first four months is $Rs.\,2750$ for the next three months is $Rs.\,2940$ and for the last five months is $Rs.\,3130.$ If the family saves $Rs.\,5330$ throughout year, find the average monthly income of the family for that year. (in $Rs.$)

A person travelled from one place to another at an average speed of $40 \,km / h$ and back to the original place at an average speed of $50\, km / h$. What is his average speed in $km / h$ during the entire trip?

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