Question

Question #feace

Answer 1

0.4 is the difference between the grade of the two students.

Explanation:

The average grade of the first 24 students was 7.2, That means that the sum of all the grades divided by 24 is equal to 7.2. When recalculating averages, we can use that to mean as if all students so far got the same grade of 7.2. Since we are adding two results to that average (total of 26 now), we can write the following equation:

`(24xx7.2+7.65+x)/26=7.25`

`180.45+x=7.25xx26`

`x+180.45=188.5`

`x=188.5-180.45`

`x=8.05`

This means that the grade achieved by the second student was 8.05. The question asks us what is the difference in the grade of the two extra students so:

`8.05-7.65=color(red)0.4 larr` difference between the two students