The average of two numbers is $62$. If $2$ is added to the smaller number,the ratio between the numbers becomes $1:2$. The smaller number is

In a school with $600$ students,the average age of the boys is $12$ $years$ and that of the girls is $11$ $years$. If the average age of the school is $11$ $years$ and $9$ $months$,then the number of girls in the school is:

The average height of the students of a class of $20$ is $105 \, cm$. If ten more students of average height of $120 \, cm$ join this class,the average height of the class will become (in $cm$)?

Out of $9$ persons,$8$ persons spent $Rs. 30$ each for their meals. The ninth one spent $Rs. 20$ more than the average expenditure of all the nine. The total money spent by all of them was (in $Rs.$)

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:

The total marks obtained by a student in Physics,Chemistry and Mathematics together is $120$ more than the marks obtained by him in Chemistry. What is the average marks obtained by him in Physics and Mathematics together?