Question

Arithmetic mean of marks (out of 25) scored by 10 students was 15 one of the student named krishma enquired The Other 9 students and find the diviations form her marks are noted as -8,-6,-3,-1,0,2,3,4,6 find karishma marks

Answer 1

Given,
Arithmetic mean = 15
Number of students =10
Deviations of nine students excluding karishma= -8,-6,-3,-1,0,2,3,4,6
Sum of deviations = -3
Arithemetic mean = d + (Summation of deviations)/(total frequency)
Let karishma's marks be x
d = x
By putting the values
15 = x + (-3 / 10)
15 + 3/10 = x
x = (150 + 3)/10
   = 153/10=15.3

Karishma got 15.3 out of 25.
Hence , her percentage marks being (marks obtained/full marks * 100) = 61.2% 

Answer 2

Step-by-step explanation:

d) Name the students, who scored 8 Marks.