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Let  be the mean and  be the standard deviation of the distribution x i 0 1 2 3 4 5 f i k + 2 2k k 2 – 1 k 2 – 1 k 2 + 1 k – 3 where  f i = 62. If [ x ] denotes the greatest integer  x , then [  2 +  2 ] is equal to -

1. 9
2. 8
3. 7
4. 6

Correct answer: 8

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