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NTA Abhyas JEE Main2020MathematicsStatisticsPractice

A number equal to 2 times the mean and with a frequency equal to k is inserted in a data having n observations. If the new mean is 4 3 times the old mean, then the value of k n is

Correct answer

0.5

Step-by-step solution

x ¯ n e w = 4 3 x ¯ From given information x ¯ n e w = n x ¯ + 2 k x ¯ n + k = 4 3 x ¯ ⇒ 3 n + 6 k = 4 n + 4 k ⇒ 2 k = n ⇒ k n = 0 . 5

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