1)Some states now allow online gambling. As a marketing manager for a casino, you need to determine the percentage of adults in those states who gamble online. How many adults must you survey in order to be 99% confident that your estimate is in error by no more than four percentage points?

a)Assume that nothing is known about the percentage of adults who gamble online.

n=(Round up to the nearest integer.)

b)Assume that 17% of all adults gamble online.

n=(Round up to the nearest integer.)

2)Here are summary statistics for the weights of Pepsi in randomly selected cans:

n=36, x=0.82407 lb, s=0.00567 lb. Use a confidence level of 99% to complete parts (a) through (d) below.

a. Identify the critical value t/2 used for finding the margin of error.

t/2=

(Round to two decimal places as needed.)

b. Find the margin of error.

E=(Round to five decimal places as needed.)

c. Find the confidence interval estimate of .

lb<<(Round to five decimal places as needed.)

d.Do a brief statement that interprets the confidence interval. Choose the correct answer below.

A.One has 99 %confidence that the sample mean weight of Pepsi in a can is equal to the population mean weight of Pepsi in a can.

B.There is a 99% chance that the true value of the population mean weight of Pepsi in a can will fall between the lower bound and the upper bound.

C.One has 99%confidence that the interval from the lower bound to the upper bound contains the true value of the population mean weight of Pepsi in a can.

D.Approximately 959%of sample mean weights of Pepsi in a can will fall between the lower bound and the upper bound.

3)Claim: More than 7.8% of homes have only a landline telephone and no wireless phone. Sample data: A survey by the National Center for Health Statistics showed that among 15,386 homes 5.77% had landline phones without wireless phones. Complete parts (a) and (b).

a. Express the original claim in symbolic form. Let the parameter represent a value with respect to homes that have only a landline telephone and no wireless phone.

p>

(Type an integer or a decimal. Do not round.)

b. Identify the null and alternative hypotheses.

H0:

H1:

(Type integers or decimals. Do not round.)

4)Use the results from a survey of a simple random sample of 1046 adults. Among the 1046 respondents, 64% rated themselves as above-average drivers. We want to test the claim that 11/20 of adults rate themselves as above-average drivers. Complete parts (a) through (c).

a. Identify the actual number of respondents who rated themselves as above-average drivers.(Round to the nearest whole number as needed.)

b. Identify the sample proportion and use the symbol that represents it.

(Use an integer or a decimal rounded to two decimal places as needed.)

c. For the hypothesis test, identify the value used for the population proportion and use the symbol that represents it.

(Use an integer or a decimal rounded to two decimal places as needed.)

5) In a newspaper survey of 491 people, 55% said that we should replace passwords with biometric security, such as fingerprints. The accompanying Statdisk display results from a test of the claim that half of us say that we should replace passwords with biometric security. Use the normal distribution as an approximation to the binomial distribution. Use the display and a 0.01 significance level to complete parts (a) through (e).

Sample proportion: 0.5498982

Test Statistic, z: 2.2113

Critical z:

2.5758

P-value: 0.0270

a. Is the test two-tailed, left-tailed, or right-tailed?

b. What is the test statistic?

z=(Round to two decimal places as needed.)

c. What is the P-value?

P-value=

(Round to three decimal places as needed.)

d. What is the null hypothesis, and what do you conclude about it?

The null hypothesis is H0:p where p denotes the population proportion of people who say that we should replace passwords with biometric security. _______ the null hypothesis.(Type an integer or a decimal. Do not round.)

e. What is the final conclusion? There ____sufficient evidence to ______ of the claim that half of us say that we should replace passwords with biometric security.