Respuesta :
Answer:
a: 68.08
b: 5.3065
Step-by-step explanation:
The point estimate is a single value. The point estimate for the mean is the mean of the sample. In this case, the mean is the sum of the values divided by the total number of values. The point estimate is the standard deviation of the sample. The standard deviation is the square root of the variance.
See the attached photo for the calculations of these values.

The point estimates for the mean and standard deviation of the given data set is respectively; 68 and 17.6.
What is a point Estimate?
A) In order to find the point estimate of the mean, we will add up the data and divide it by the number of values.
Here,
∑x = 57 + 61 + 86 + 74 + 72 + 73 + 20 + 57 + 80 + 79 + 83 + 74
= 816
n = 12 numbers
Thus;
Mean = ∑x/n
= 816/12
Mean = 68
B) In order to find the estimate of the standard deviation, we have the formula;
s = √[(n*(∑x²) - (∑x)²)/n(n - 1)]
∑x² = 57² + 61² + 86² + ... + 74²
= 59,010
s = √[ (12*(59,010) - (816)²)/(12)(11)]
s = 17.6
Hence, The point estimates for the mean and standard deviation of the given data set is respectively; 68 and 17.6.
Learn more about estimation here:
https://brainly.com/question/6844110
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