Average of marks of 28 students in Mathematics was 50 . 8 students left school, then this average in

English

Gujarati

Hindi

4.Average

easy

The average of marks of $28$ students in Mathematics was $50 .$ $8$ students left the school, then this average increased by $5 .$ What is the average of marks obtained by the students who left the school?

A

$50.5$

B

$37.5$

C

$42.5$

D

$45$

Solution

Total marks of $28$ students $=28 \times 50=1400$ Total marks of $20$ students $=20 \times 55=1100$ Total marks of $8$ students $=1400-1100=300$

Average of $8$ students $=\frac{300}{8}=37.5$

Standard 13

Quantitative Aptitude

Share

Similar Questions

The average salary of the entire staff in a office is $Rs.\, 120$ per $month.$ The average salary of officers is $Rs.\, 460$ and that of non-officers is $Rs. \,$ $110 .$ If the number of officers is $15,$ then find the number of non-officers in the office ?

medium

The average of consecutive numbers is $n .$ If the next two consecutive numbers are also included, the average of the five numbers will

medium

The average age of three boys is $15$ $year.$ If the ratio of their ages is $3:5: 7,$ what is the age of the oldest boy in $year$?

medium

The average of marks obtained by $100$ candidates in a certain examination is $30 .$ If the average marks of passed candidates is $35$ and that of the failed candidates is $10,$ what is the number of candidates who passed the examination?

medium

$10$ $years$ ago the average age of all the $25$ $teachers$ of the Girls college was $45\, years.$ $4 \,years$ ago, the principal has retired from her post at the age of $60 \,year.$ So after one year a new principal whose age was $54 \,years$ recruited from outside. The present average age of all the teachers is, if principal is also considered as a teacher

hard