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The Mean of Marks Scored by 100 Students Was Found to Be 40. Later on It Was Discovered that a Score of 53 Was Misread as 83. Find the Correct Mean. - Mathematics

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प्रश्न

The mean of marks scored by 100 students was found to be 40. Later on it was discovered
that a score of 53 was misread as 83. Find the correct mean.

उत्तर

Mean marks of 100 students = 40
  ⇒Sum of marks of 100 students 100×40×4000

Correct value 53.
Incorrect value 83. 
Correct sum = 4000-83+53
                   = 3970

∴ Correct mean =`3970/100`

                        = 39.7

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अध्याय 24: Measures of Central Tendency - Exercise 24.1 [पृष्ठ ९]

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आरडी शर्मा Mathematics [English] Class 9
अध्याय 24 Measures of Central Tendency
Exercise 24.1 | Q 12 | पृष्ठ ९

वीडियो ट्यूटोरियलVIEW ALL [1]

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