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chatgpt response? ... smart :cool:
Dereno
Bunuel
If the mean of list A is 6.8 and the standard deviation is 3.6, then how many elements of list A are within 1 unit of standard deviation of the mean?

A = {2, 9, 2, 6, 9, 10, 7, 4, 5, 14}

A. 3
B. 4
C. 5
D. 6
E. 7


­
To find how many elements of list A are within 1 unit of standard deviation of the mean, we can follow these steps:
  1. Identify the mean and standard deviation:
    Given:

    • Mean μ = 6.8
    • Standard deviation σ = 3.6
  2. Define the range within 1 standard deviation:
    The range within 1 standard deviation of the mean is:
    μ−σ≤x≤μ+σ

    Substituting the values, we get 6.8−3.6 ≤ x ≤ 6.8+3.63.2 ≤ x ≤ 10.4
  3. Check how many elements in A are within this range:

    A={2,9,2,6,9,10,7,4,5,14} We now check each element to see if it falls within the range [3.2,10.4]

    [3.2,10.4].

    • 2: Not within the range.
    • 9: Within the range.
    • 2: Not within the range.
    • 6: Within the range.
    • 9: Within the range.
    • 10: Within the range.
    • 7: Within the range.
    • 4: Within the range.
    • 5: Within the range.
    • 14: Not within the range.
  4. Count the elements within the range:
    The elements within the range [3.2,10.4] are 9,6,9,10,7,4,5, which makes 7 elements.
Thus, there are 7 elements of list A within 1 unit of standard deviation of the mean.
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Given: Mean= 6.8
SD= 3.6
Within range of 1 SD Means values that are low between (Mean-1 SD) and (Means+1 SD)
(6.8-3.6) And (6.8+3.6)
(3.2) And (10.4) Values that are between these ranges are the values that lies within 1 SD of mean.
There are total 7 values (9,6,9,10,7,4,5) that lies between 3.2 and 10.4

Answer: E
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Range of 1SD = 6.8-3.6 <=A<=6.8+3.6
3.2<=A<=10.4
Elements in the range in A = {2, 9, 2, 6, 9, 10, 7, 4, 5, 14} = 7 elements

Bunuel
If the mean of list A is 6.8 and the standard deviation is 3.6, then how many elements of list A are within 1 unit of standard deviation of the mean?

A = {2, 9, 2, 6, 9, 10, 7, 4, 5, 14}

A. 3
B. 4
C. 5
D. 6
E. 7


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