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A Bell Curve (Normal Distribution) has a mean of − 1 and a standard de
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21 Sep 2021, 01:13
21 Sep 2021, 01:13
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A Bell Curve (Normal Distribution) has a mean of − 1 and a standard deviation of 1/8 . How many integer values are within three standard deviations of the mean?
A. 0
B. 1
C. 3
D. 6
E. 7
A. 0
B. 1
C. 3
D. 6
E. 7
Re: A Bell Curve (Normal Distribution) has a mean of − 1 and a standard de
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21 Sep 2021, 06:04
21 Sep 2021, 06:04
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3 Standard Deviations from mean will be -1 + 3/8 or -1 - 3/8, right and left side of the bell curve.
The only integer value is -1 and answer is B)
The only integer value is -1 and answer is B)
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Re: A Bell Curve (Normal Distribution) has a mean of − 1 and a standard de
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21 Sep 2021, 06:08
21 Sep 2021, 06:08
1
Carcass wrote:
A Bell Curve (Normal Distribution) has a mean of − 1 and a standard deviation of 1/8 . How many integer values are within three standard deviations of the mean?
A. 0
B. 1
C. 3
D. 6
E. 7
A. 0
B. 1
C. 3
D. 6
E. 7
Mean = -1
Standard Deviation = 1/8
1 unit of standard deviation BELOW the mean = -1 - 1/8 = -1 1/8
2 units of standard deviation BELOW the mean = -1 - 1/8 - 1/8 = -1 2/8
2 units of standard deviation BELOW the mean = -1 - 1/8 - 1/8 - 1/8 = -1 3/8
1 unit of standard deviation ABOVE the mean = -1 + 1/8 = -7/8
2 units of standard deviation ABOVE the mean = -1 + 1/8 + 1/8= -6/8
3 units of standard deviation ABOVE the mean = -1 + 1/8 + 1/8 + 1/8= -5/8
So, all values from -1 3/8 to -5/8 are within 3 standard deviations of the mean.
Within this range, there is only 1 integer value: -1
Answer: B
