Question

1.) A university dean is interested in determining the proportion of students who receive some sort of financial aid. Rather than examine the records for all​ students, the dean randomly selects 200 students and finds that 118 of them are receiving financial aid. Use a 95​% confidence interval to estimate the true proportion of students who receive financial aid.

a.) 0.59+/-0.068

b.) 0.59+/-0.005

c.) 0.59+/-0.002

d.)0.59+/-0.474

2.)

Fill in the blanks. The owner of​ Get-A-Away Travel has recently surveyed a random sample of 479 customers to determine whether the mean age of the​ agency's customers is over 31. The appropriate hypotheses are H0​=31​, Ha: μ>31. If he concludes the mean age is over 31 when it is​ not, he makes a​ __________ error. If he concludes the mean age is not over 31 when it​ is, he makes a​ __________ error.

a.) Type II; Type II

b.) Type I; Type II

c.) Type I; Type I

d.) Type II; Type I

Answer 1

Ans:

1)

Point estimate=118/200=0.59

Margin of error=1.96*SQRT(0.59*(1-0.59)/200)=0.068

Option a is correct.

0.59+/-0.068

2)

Correct option is b:

Type I; Type II

If he concludes the mean age is over 31 when it is​ not, he makes a​ type I error. If he concludes the mean age is not over 31 when it​ is, he makes a​ type II error.

(as type I error is to reject the null hypothesis,when null hypothesis is true)

(as type II error is to fail to reject the null hypothesis,when null hypothesis is false)