Question
The average of 10 observations is 46. It was realized
later that an observation was misread as 42 in place of 142. The correct average is:Solution
Sum of all numbers = 46 × 10 = 460 Correct sum = 460 - 42 + 142 ⇒ 602 - 42 ⇒ 560 Correct Average = 560/10 ⇒ 56 ∴ The correct average is 56.
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