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For the set {6, 15, y}, the standard deviation is x. What is the standard deviation of the set {10, 19, (y + 4)

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by BTGmoderatorDC » Thu Oct 01, 2020 5:29 pm
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For the set {6, 15, y}, the standard deviation is x. What is the standard deviation of the set {10, 19, (y + 4)}?

A. x
B. x + 4/3
C. x + 4
D. x + 12
E. Cannot be determined from the information provided


OA A

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Re: For the set {6, 15, y}, the standard deviation is x. What is the standard deviation of the set {10, 19, (y + 4)

by DHRJ007 » Fri Oct 02, 2020 2:12 am
adding a constant to all elements of a set will have no effect on standard deviation.
so,

ans:A
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Re: For the set {6, 15, y}, the standard deviation is x. What is the standard deviation of the set {10, 19, (y + 4)

by Scott@TargetTestPrep » Mon Oct 05, 2020 6:58 am
BTGmoderatorDC wrote: ↑
Thu Oct 01, 2020 5:29 pm
 For the set {6, 15, y}, the standard deviation is x. What is the standard deviation of the set {10, 19, (y + 4)}?

A. x
B. x + 4/3
C. x + 4
D. x + 12
E. Cannot be determined from the information provided


OA A

Solution:

Since each number in the second set is 4 more than each number in the first set, the standard deviations of both sets must be the same. Therefore, the standard deviation of the second set is also x.

Answer: A

Scott Woodbury-Stewart
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Re: For the set {6, 15, y}, the standard deviation is x. What is the standard deviation of the set {10, 19, (y + 4)

by Scott@TargetTestPrep » Tue Oct 06, 2020 3:14 am
BTGmoderatorDC wrote: ↑
Thu Oct 01, 2020 5:29 pm
 For the set {6, 15, y}, the standard deviation is x. What is the standard deviation of the set {10, 19, (y + 4)}?

A. x
B. x + 4/3
C. x + 4
D. x + 12
E. Cannot be determined from the information provided


OA A

Solution:

If each element of a data set has the same number added to it, the standard deviation of the data set doesn’t change. Since each number in the second set is 4 more than each number in the first set, the standard deviations of both sets must be the same. Therefore, the standard deviation of the second set is also x.

Answer: A

Scott Woodbury-Stewart
Founder and CEO
[email protected]

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