The average of $100$ observations was calculated as $35$. It was found later that one of the observations was misread as $83$ instead of $53$. The correct average is: (in $.7$)

If the mean of $a, b, c$ is $M$ and $ab + bc + ca = 0$,then the mean of $a^2, b^2, c^2$ is

The average temperature from Monday to Thursday is $48^{\circ} C$ and from Tuesday to Friday,the average temperature is $52^{\circ} C$. If the temperature on Monday is $42^{\circ} C$,what was the temperature on Friday in $^{\circ} C$?

The average weight of five persons sitting in a boat is $38\, kg$. The average weight of the boat and the persons sitting in the boat is $52\, kg$. What is the weight of the boat (in $kg$)?

The average of three numbers is $135$. The largest number is $195$ and the difference between the other two is $20$. The smallest number is:

Of the three numbers,the first is twice the second and the second is thrice the third. If the average of the three numbers is $10$,the numbers are