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If the mean of x₁, x₂,..., xₙ is xbar, then the mean of the new data x_i + 2i for i = 1, 2,..., n is:

1. xbar + n
2. xbar + n + 1
3. xbar + 2
4. xbar + 2n

Correct answer: xbar + n + 1

Solution

Adding 2i shifts the mean by the average of 2i, which is (n+1), so the new mean is xbar + (n+1).

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