The average temperature from Monday to Wednesday is $37^{\circ}C$,while the average temperature from Tuesday to Thursday is $34^{\circ}C$. The temperature of Thursday is $\frac{4}{5}$ times that of Monday. Find the temperature of Thursday in $^{\circ}C$.

The average age of a group of $9$ students is $20\, \text{years}$. When $6$ more students joined the group,the average age falls by $2\, \text{years}$. The average age of the new students is:

There are $6$ consecutive odd numbers in increasing order. The difference between the average of the squares of the first $4$ numbers and the last $4$ numbers is $64$. If the sum of the squares of the first and the last element is $178$,then the average of all the $6$ numbers is:

The average pocket money of $3$ friends $A, B,$ and $C$ is $Rs. 80$ per month. If $B$ spends double and $C$ spends triple of what $A$ spends during that month,and if the average of their unspent pocket money is $Rs. 60,$ then how much does $A$ spend (in $Rs.$)?

The average age of $15$ students in a class is $15 \text{ years}$. Out of these,the average age of $5$ students is $14 \text{ years}$ and that of the other $9$ students is $16 \text{ years}$. What is the age of the $15^{th}$ student? (in $\text{years}$)

The mean weight of $34$ students of a school is $42\, kg$. If the weight of the teacher is included, the mean weight increases by $400\, g$. Find the weight (in $kg$) of the teacher.