If d is the standard deviation x, y, and z, what is the standard deviation of x + 5, y + 5, z + 5 ?

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If d is the standard deviation x, y, and z, what is the standard deviation of x + 5, y + 5, z + 5 ?

A. d
B. 3d
C. 15d
D. d + 5
E. d + 15



OA A

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BTGmoderatorDC wrote:
Tue Jan 25, 2022 5:48 pm
If d is the standard deviation x, y, and z, what is the standard deviation of x + 5, y + 5, z + 5 ?

A. d
B. 3d
C. 15d
D. d + 5
E. d + 15



OA A

Source: GMAT Prep
Adding the same value to each value in a set does not change the standard deviation of the set.

So, the standard deviation of {x + 5, y + 5, z + 5 } will also be d.

Answer: A
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