Answer
13. a. The mean of the data will become 35 while the standard deviation remained the same when 5 points is added to every score in the population because each of the deviation scores ( X-$\mu$) does not change(σ=5).
b. The new mean of the data will change to 90 while the standard deviation will change to 15 when each score is multiplied by 3. This is because multiplying each score causes each distance to be multiplied, so the standard deviation also is multiplied by the same amount.
Work Step by Step
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