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NTA Abhyas JEE Main2020MathematicsStatisticsPractice

The marks obtained by 9 students in a chemistry test are 50,69,20,33,53,39,40,65 and 59 . If the mean deviation about the median of this data is λ , then the value of 9 λ 10 is equal to

Correct answer

11.4

Step-by-step solution

20,33,39,40,50,53,59,65,69 Median, M = 9 + 1 2 t h observation = 5 t h observation = 50 The absolute values of respective deviations from the median is 30,17,11,10,0 , 3,9 , 15,19 ∴ ∑ i = 1 9 x i - M = 114 Mean deviation about M = 1 9 ∑ i = 1 9 x i - M = 1 9 × 114 i.e λ = 114 9 ⇒ 9 λ 10 = 11 . 4

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