Question

15. The mean of a hundred observations was found to be 40. Later on, it was discovered that a
score of 27 was misread as 57. Find the correct mean.
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Answer 1

Step-by-step explanation:

(57 + x)= 4000x

= 3943(3943+27)/100

= 3970/100

=397/10

=39.7  More

Answer 2

Step-by-step explanation:

mean of 100 observations = 40

sum of 100 observations = 40*100 = 4000

one score was misread as 57 in place of 27.

actual sum = 4000 - 57 + 27

= 3970

correct mean = 3970/100

= 39.70