Question

In 1898 the United States and Spain fought a war over the U.S. intervention in the Cuban War of Independence. At that time the U.S. military was concerned about the nutrition of its recruits. Many did not have a sufficient number of teeth to chew the food provided to soldiers. As a result, it was likely that they would be undernourished and unable to fulfill their duties as soldiers. The require-ments at that time specified that a recruit must have "at least four sound double teeth, one above and one below on each side of the mouth, and so opposed" so that they could chew food. Of the 58953 recruits who were under the age of 20, 63 were rejected for this reason. For the 43786 recruits who were 40 or over, 3829 were rejected.

(a) Find the proportion of rejects for each age group ( ±± 0.0001).

pˆ<20p^<20 =

pˆ40+p^40+ =

(b) Find a 99% confidence interval ( ±± 0.001) for the difference in the proportions.

A 99% confidence interval is from to

(c) Use a significance test to compare the proportions ( ±± 0.001)

pˆp^ =

zz =

PP -value =

Conclusion

We have evidence to conclude there was an age group difference in the rejection rate

OR

We have no evidence to conclude that there was an age group difference in the rejection rate

Answer 1

Find the sample proportions using the given information. Create a 99% confidence interval using the sample proportions you just find in the above part. Now, calculate the test statistic and p-value to make a decision for the claim. Finally, make a conclusion for the claim.