The mean of 8 article was found to be 15. On rechecking, it was found that two article were wrongly taken as 11 and 9 instead of 16 and 14 respectively. Find the correct mean. A) 17.25 B) 13.65 C) 16.54 D) 16.25

1 Answer

Answer :

D)

Calculated mean of 8 articles = 15

Incorrect sum of these 8 articles = (15*8) = 120.

Correct sum of these 8 articles

= (incorrect sum) - (sum of incorrect articles) + (sum of actual articles)

= [120 - (20) + (30)]

= 130

Therefore, correct mean = 130/8 = 16.25

Hence, the correct mean is 16.25.

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