Question
The average age of a group of 25 persons is found
to be 30 years. Later it is found that age of two of the persons is calculated as 32 and 60 instead of 80 and 12. Find the correct average age of the group.Solution
Required average = {(25 × 30) – 32 – 60 + 80 + 12}/25 = 30 years
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