Approximately 20% of newborns are born more than 1 week before their due date. A random sample of 20 newborns is selected.The standard deviation of the sampling distribution for the proportion of your sample that is born more than 7 days before their due date is(A) 0.20(B) 3.2(C) 0.089(D) 0.008
Q. Approximately 20% of newborns are born more than 1 week before their due date. A random sample of 20 newborns is selected.The standard deviation of the sampling distribution for the proportion of your sample that is born more than 7 days before their due date is(A) 0.20(B) 3.2(C) 0.089(D) 0.008
Identify Proportion: First, we need to identify the proportion of newborns born more than 1 week early, which is 20% or 0.20.
Calculate Standard Deviation: Next, we calculate the standard deviation of the sampling distribution for the proportion using the formula for the standard deviation of a sample proportion: Standard deviation = (p×(1−p))/nwhere p is the proportion and n is the sample size.
Plug in Values: Plug in the values: p=0.20 and n=20.Standard deviation = (0.20×(1−0.20))/20
Do the Calculation: Do the calculation:Standard deviation = (0.20×0.80)/20Standard deviation = 0.16/20Standard deviation = 0.008
Calculate Square Root: Finally, calculate the square root of 0.008. Standard deviation = 0.008≈0.089 (rounded to three decimal places).
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