A consumer advocate wants to collect a sample of jelly jars and measure the actual weight of the product in the container. He needs to collect enough data to construct a confidence interval with a margin of error of no more than 3 grams with 95% confidence. The standard deviation of these jars is usually 3 grams. Estimate the minimum sample size required.
Accepted Solution
A:
Answer:n=3.8416≅4So Minimum Sample Size is 4Step-by-step explanation:In order to find the minimum sample size, the formula we use will be:[tex]n= \frac{Z^2*S^2}{E^2}[/tex]Where:n is sample size Z is the distribution S is the standard deviationE is the Margin of errorS=3 ,E=3For Z:Alpha=1-0.95=0.05Alpha/2=0.025=2.5%From Cumulative Standard Distribution Table:Z at Alpha/2 = 1.960[tex]n= \frac{1.960^2*3^2}{3^2}[/tex]n=3.8416≅4So Minimum Sample Size is 4