There were $35$ students in a hostel. If the number of students is increased by $7,$ the expenditure on food increase by $Rs. \,42$ per $day$ while the average expenditure of students is reduced by $Rs.\, 1.$ What was the initial expenditure on food per day? (in $Rs.$)

The average age of $30$ women decreases by $3$ $months$ if a new person Neha is included in place of a $25\, year$ old woman. Calculate the age of Neha in $year$ ?

The average of three numbers is $28 .$ If first number is half of the second and the $3^{rd}$ number is twice the second, then the third number is?

The average weight of $24$ students is $35\, kgs.$ If the weight of teacher is added the average increased by $400\, gms$. What is the weight of the teacher? (in $kg$)

The daily maximum temperature in Delhi, for $7$ consecutive days in $May \,1988 ,$ were $42.7^{\circ} C , 44.6^{\circ} C$, $42.0^{\circ} C , 39.1^{\circ} C , 43.0^{\circ} C , 42.5^{\circ} C$ and $38.5^{\circ} C$. Find out the average daily maximum temperature. (in $^{\circ} C$)