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Let x(1), x(2), ….., x(n) be n observati...

Let `x_(1), x_(2), ….., x_(n)` be n observations. Let `w_(i) = lx_(i) + k` for I = 1, 2,…., n, where l and k are constants. If the mean of `x_(i)`'s is 48 and their standard deviation is 12, the mean of `w_(i)`'s is 55 and standard deviation of `w_(i)`'s is 15, the values of l and k should be

A

l = 1.25, k = - 5

B

l = - 1.25, k = 5

C

l = 2.5, k = - 5

D

l = 2.5, k = 5

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The correct Answer is:
A
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