Mathematics
The mean of 100 observations is 50. If one of the observations was misread as 50 instead of 40, the correct mean is :
40
49.9
50
50.1
Measures of Central Tendency
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Answer
Sum of observations when observations were misread = Number of observations × Initial Mean
= 100(50)
= 5000
To find the correct sum We need to subtract the wrong value and add the correct value,
Sum = 5000 - 50 + 40
= 4990
∴ Mean = = 49.9
Hence, option 2 is the correct option.
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