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Consider the data on x taking the values 0, 2, 4, 8,..., 2ⁿ with frequencies ^nC₀, ^nC₁, ^nC₂,..., ^nCₙ respectively. If the mean of this data is 728/2ⁿ, then n is equal to _________.
- 6
- 7
- 8
- 9
Correct answer: 6
Solution
The mean is calculated by taking the weighted average of the values of x, where the weights are given by the frequencies. Given that the mean is 728/2ⁿ, and knowing the relationship between the values and their frequencies, we can derive that n must be 6 to satisfy this mean.
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