Solution:
Given ,
= 25 ..Population SD
E = 3.4 Margin of error
c = 90% = 0.90 ...confidence level
= 1- c = 1- 0.90 = 0.10
/2 = 0.05
Using Z table ,
= 1.645
Now, sample size (n) is given by,
= {(1.645* 25 )/ 3.4 }2
= 146.30
= 147 ..(round to the next whole number)
Answer is
147
2 1 pts Question 6 6) How many women must be randomly selected to estimate the...
6) How many women must be randomly selected to estimate the mean weight of women in one age group. We want 90% confidence that the sample mean is within 3.4 lb of the population mean, and the population standard deviation is known to be 25 lb.
QUESTION 6 Use the given information to find the minimum sample size required to estimate an unknown population mean μ. How many women must be randomly selected to estimate the mean weight of women in one age group. We want 90% confidence that the sample mean is within 3.4 lb of the population mean, and the population standard deviation is known to be 25 lb 208 148 145 147
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