Question

The nutrition label for Oriental Spice Sauce states that one package of sauce has 1000 milligrams of sodium. To determine if the label is accurate, the FDA randomly selects 120 packages of Oriental Spice Sauce and determines the sodium content. The sample has an average of 1002.51 milligrams of sodium per package with a sample standard deviation of 230.57 milligrams.

Step 1 of 2 :  

Calculate a 95%95% confidence interval for the mean sodium content in Oriental Spice Sauce.

Answer 1

df = n - 1 = 120 - 1 = 119

From T table,

t critical value at 0.05 significance level with 119 df = 1.980

95% confidence interval for is

- t * S / sqrt(n) < < + t * S / sqrt(n)

1002.51 - 1.98 * 230.57 / sqrt(120) < < 1002.51 + 1.98 * 230.57 / sqrt(120)

960.83 < < 1044.19

95% CI is ( 960.83 , 1044.19 )