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Confidence Interval

Please provide step by step instructions using actual numbers instead of formulas for solving the following 3 problems, thanks

3. Determine whether the average number of calories in a homemade cookie is more than a store-bought one. Estimate the difference in the mean calories between the two types using a 90% confidence interval.
homemade n=40 x-bar=180 s=2
storebought n=45 x-bar=179 s=4

4. A childcare agency was interestin in examining the amount that families pay per child per month for childcare outside the home. A randome sample of 64 families was selected and the mean and the standard deviation were computed to be $675 and $80 respectively.
a. Find a 95% confidence interval for the true average amount spent per child per month for childcare outside the home.
b. Interpret the interval found in part a.
c. A social worker claims that the average amount spent per child per month outside the home is $700. Based on the interval in part a can this claim be rejected?
d. Find a 95% upper confidence bound for the true average amount spent per child per month on childcare outside the home.

Solution Summary

Please provide step by step instructions using actual numbers instead of formulas for solving the following 3 problems, thanks

3. Determine whether the average number of calories in a homemade cookie is more than a store-bought one. Estimate the difference in the mean calories between the two types using a 90% confidence interval.
homemade n=40 x-bar=180 s=2
storebought n=45 x-bar=179 s=4

4. A childcare agency was interestin in examining the amount that families pay per child per month for childcare outside the home. A randome sample of 64 families was selected and the mean and the standard deviation were computed to be $675 and $80 respectively.
a. Find a 95% confidence interval for the true average amount spent per child per month for childcare outside the home.
b. Interpret the interval found in part a.
c. A social worker claims that the average amount spent per child per month outside the home is $700. Based on the interval in part a can this claim be rejected?
d. Find a 95% upper confidence bound for the true average amount spent per child per month on childcare outside the home.

$2.19