Question

10. Arithmetic mean of marks (out of 25) scored by 10 students was 15. One of the student
named Karishma enquired the other 9 students and find the deviations from her marks are
noted as - 8. - 6. – 3. – 1,0.2.3.4.6. Find Karishma's marks​

Answer 1

Answer:

Let Krishna's marks be x marks.

x

ˉ

=15

n=10

∑x=x+x−8+x−6+x−3+x−1+x+x+2+x+3+x+4+x+6=10x−3

15=

10

10x−3

150+3=10x

x=

10

153

=15.3 marks.

∴ Krishna scored 15.3 marks