Maharashtra State Board course SSC (English Medium) Class 9
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The Calculated Mean of 50 Observations Was 80. It Was Later Discovered that Observation 19 Was Recorded by Mistake as 91. What Was the Correct Mean? - Algebra

ConceptMeasures of Central Tendency

Question

The calculated mean of 50 observations was 80. It was later discovered that observation 19 was recorded by mistake as 91. What was the correct mean?

Solution

It was later discovered that observation 19 was recorded by mistake as 91. What was the correct mean?
We have,
The calculated mean of 50 observations was 80.
The total incorrect sum of the observations = 80 x 50 = 4000The total correct sum of the observations = 4000 - 19 + 91 = 4072
So, the correct mean = 4072/50 = 81.44

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Balbharati Solution for Balbharati Class 9 Mathematics 1 Algebra (2019 to Current)
Chapter 7: Statistics
Practice set 7.5 | Q: 7 | Page no. 125
Solution The Calculated Mean of 50 Observations Was 80. It Was Later Discovered that Observation 19 Was Recorded by Mistake as 91. What Was the Correct Mean? Concept: Measures of Central Tendency.
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