Question

the mean of marks scored by 50 students was found to be 39. Later, it was found that a score of 75 was misread as 25. Find the correct mean

Answer 1

Answer:

correct mean = 40

Step-by-step explanation:

mean=39

n=50

total marks =50 x 39

= 1950

correct total = total - wrong observation + correct observation

= 1950 - 25 + 75

= 1950+50

=2000

correct mean = total / no. of terms

= 2000/50

= 40