Question

The average marks of 7 students are 42%. When a student joined this group then
the average is increased to 48%. Find the marks of the student who joined ?​

Answer 1

Answer:

90%

Step-by-step explanation:

8×48-7×42

384-294

90

Answer 2

Given:

The average mark of 7 students in a class is 42%.

Increased average = 48%

To find:

Marks of the new student.

Solution:

The formula for average is,

Average = $\frac{Sum of all terms}{ total number of terms}$

Average marks of seven students = 42

Using the formula for average,

Total marks of seven students = Average marks × number of students in the class

Total marks = 42 × 7 = 294

Increased average = 48%

Total students after a new student joined the class = 8

Total marks of 8 students = 48 × 8 = 384

Marks of the new student = Total marks of 8 students = total marks of 7 students

= 384 - 294

= 90

Hence, the marks of the new student = 90