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The standard deviation of the dataset 10, 20, 30
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29 Jul 2018, 04:37
29 Jul 2018, 04:37
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39% (00:43) wrong based on 171 sessions
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Quantity A |
Quantity B |
The standard deviation of the dataset 10, 20, 30 |
The standard deviation of the dataset 10, 20, 20, 20, 20, 20, 30 |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
Re: The standard deviation of the dataset 10, 20, 30
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05 Aug 2018, 14:26
05 Aug 2018, 14:26
1
We do not need to work this out till the very end.
A: average= 20. x-average= -10,0,10 respectively. Square the differences- 100, 0, 100. Average of the squared differences- 200/3. Standard deviation= sqroot (200/3)
B: average=20. x-average= -10, 0,0,0,0,0, 10 respectively. Square the differences- 100, 0,0,0,0,0,100. Average of squared differences- 200/7. Standard deviation= sqroot(200/7).
Since denominator of A is smaller than that of B, A will be the larger value.
I also understand this is a very time consuming, tedious, long method. So if someone has a quicker way, please help
A: average= 20. x-average= -10,0,10 respectively. Square the differences- 100, 0, 100. Average of the squared differences- 200/3. Standard deviation= sqroot (200/3)
B: average=20. x-average= -10, 0,0,0,0,0, 10 respectively. Square the differences- 100, 0,0,0,0,0,100. Average of squared differences- 200/7. Standard deviation= sqroot(200/7).
Since denominator of A is smaller than that of B, A will be the larger value.
I also understand this is a very time consuming, tedious, long method. So if someone has a quicker way, please help
Re: The standard deviation of the dataset 10, 20, 30
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16 Oct 2019, 01:23
16 Oct 2019, 01:23
any easy way to do so
