In: Statistics and Probability
The nutrition label for Oriental Spice Sauce states that one package of sauce has 1050 milligrams of sodium. To determine if the label is accurate, the FDA randomly selects 110 packages of Oriental Spice Sauce and determines the sodium content. The sample has an average of 1064.83 milligrams of sodium per package with a sample standard deviation of 248.70 milligrams. Step 1 of 2 : Calculate a 95% confidence interval for the mean sodium content in Oriental Spice Sauce.
Solution :
Given that,
= 1064.83 milligrams
s = 248.70 milligrams.
n = 110
Degrees of freedom = df = n - 1 = 110 - 1 = 109
At 95% confidence level the t is ,
= 1 - 95% = 1 - 0.95 = 0.05
/ 2 = 0.05 / 2 = 0.025
t /2,df = t0.025,109 = 1.982
Margin of error = E = t/2,df * (s /n)
= 1.982 * (248.70 / 110 )
= 47.0
Margin of error = 47.0
The 95% confidence interval estimate of the population mean is,
- E < < + E
1064.83 - 47.0 < < 1064.83 + 47.0
1017.83 < < 1111.83
(1017.83, 1111.83 )