A professional institute's total expenditure on students for a particular course is partly fixed and partly varies linearly with the number of students. The average expense per student is $Rs.\,615$ when there are $24$ students and $Rs.\,465$ when there are $40$ students. What is the average expense when there are $60$ students ? (in $Rs.$)
$370$
$450$
$350$
$390$
$10$ years ago, the average age of a family of $4$ members was $24$ $years.$ Two children having been born (with age difference of $2\, years$), the present average age of the family is the same. The present age of the youngest child is (in $years$)
A team of $8$ persons joins in shooting competition. The be marksman scored $85$ points, the average score for the team would have been $84. $ The number points the team scored was
The average marks of a student in four subjects is $75 .$ If the student obtained $80$ marks in the $5^{\text {th }}$ subject then the new average is?
In a class of $100$ students, the mean marks obtained in a subject is $30$ and in another class of $50$ students the mean marks obtained in the same subject is $60 .$ The mean marks obtained by the students of two classes taken together is
There are three baskets of fruits. The $1^{st}$ basket has twice the number of fruits in the $2^{nd}$ basket. The $3^{rd}$ basket has three-fourths of the fruits in the first. The average of the fruits in all the baskets is $30 .$ What is the number of fruits in the first basket ?