Which of the following triples of numbers have the same standard deviation as the numbers p, q, and ...

Which of the following triples of numbers have the same standard deviation as the numbers p, q, and r? I. p-2, q-2, r-2 II. 0, p-q, r-q III. p-4, q+5, r-1

Quiz

Answer/Solution

II and I only

Steps/Work

If we add or subtract a constant to each term in a set the standard deviation will not change.
Set {p-2, q-2, r-2} is obtained by subtracting 2 from each term of {p, q, r}
Set {0, p-q, r-q} is obtained by subtracting s from each term of {p, q, r}
Set {p-4, q+5, r-1} is totally different from {p, q, r}.
Thus the answer is I and II only.
Answer:D.