India Exam Junction
3. The mean of 25 observations was found to be 78.4. But later on it was found that 96 was misread as 69. The correct mean is
76.54
78.4
79.48
81.32
Correct Answer :
79.48
Solution
Correct sum = (78.4 × 25 + 96 – 69) = 1987.
Correct mean =\( {1987 \over 25} = 79.48\)