Acereal manufacturer is concerned that the boxes of cereal not be under filled or overfilled.

each box of cereal is supposed to contain 13 ounces of cereal.

a random sample of 31 boxes is tested.

the average weight is 12.58 ounces and the standard deviation is 0.25 ounces.

calculate a confidence interval to test the hypothesis at a=.10

Step-by-step explanation:

given that

A cereal manufacturer is concerned that the boxes of cereal not be under filled or overfilled.

Each box of cereal is supposed to contain 13 ounces of cereal.

A random sample of 31 boxes is tested.

The average weight is 12.58 ounces and the standard deviation is 0.25 ounces.

Sample mean = 12.58

Sample std deviation = 0.25

Sample size = 31

Sample std error =

confidence interval can be calculated using t critical value because population sd is not known.

df = 30

t critical for two tailed = 1.697

Margin of error =

conidence interval =

Since this does not contain 13 oz. we reject the claim that each box contains exactly 13 oz.

if you explain the the question more correctly i might be able to answer this better

step-by-step explanation:

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