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Consider the data on x taking the values 0 , 2 , 4 , 8 , . . . . . , 2 n with frequencies C 0 n , C 1 n , C 2 n , . . . . , C n n respectively. If the mean of this data is 728 2 n , then n is equal to ....... .

Correct answer

0

Step-by-step solution

x i (observation) 0 2 2 2 ................ 2 n f i (frequency) C 0 n C 1 n C 2 n ............. C n n x ¯ = Σ f i x i Σ f i 0 × C 0 n + 2 × C 1 n + 2 2 × C 2 n . . . . . 2 n × C n n C 0 n + C 1 n + C 2 n . . . . . + C n n = 3 n - 1 2 n = 728 2 n ⇒     3 n = 3 6 ⇒   n = 6

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