need this in 24 hrs

MAT 181-Chapter 9 Practice Problems-Q

Name___________________________________ Date: ____________

Find the number of successes x suggested by the given statement.

1) Among 780 people selected randomly from among the residents of one city, 20.38% were found to be living below the official poverty line.

A) 164 B) 158 C) 160 D) 159

Assume that you plan to use a significance level of α = 0.05 to test the claim that p1 = p2, Use the given sample sizes and numbers of successes to find the pooled estimate . Round your answer to the nearest thousandth.

2) n1 = 100 n2 = 100

x1 = 42 x2 = 45

A) 0.479 B) 0.392 C) 0.305 D) 0.435

Assume that you plan to use a significance level of α = 0.05 to test the claim that p1 = p2. Use the given sample sizes and numbers of successes to find the z test statistic for the hypothesis test.

3) n1 = 190 n2 = 184

x1 = 78 x2 = 69

A) z = 0.399 B) z = 0.703 C) z = 9.744 D) z = 18.096

4) A report on the nightly news broadcast stated that 10 out of 129 households with pet dogs were burglarized and 23 out of 197 without pet dogs were burglarized.

A) z = -1.148 B) z = -0.002 C) z = -0.459 D) z = -1.952

Solve the problem.

5) The table shows the number satisfied in their work in a sample of working adults with a college education and in a sample of working adults without a college education. Assume that you plan to use a significance level of α = 0.05 to test the claim that Find the critical value(s) for this hypothesis test. Do the data provide sufficient evidence that a greater proportion of those with a college education are satisfied in their work?

A) z = -1.645; yes B) z = 1.645; no C) z = ± 1.96; no D) z = 1.96; yes

6) The table shows the number of smokers in a random sample of 500 adults aged 20-24 and the number of smokers in a random sample of 450 adults aged 25-29. Assume that you plan to use a significance level of to test the claim that Find the critical value(s) for this hypothesis test. Do the data provide sufficient evidence that the proportion of smokers in the 20-24 age group is different from the proportion of smokers in the 25-29 age group?

A) z = ± 1.28; yes B) z = ± 1.96; no C) z = ± 1.645; yes D) z = 1.28; no

Assume that you plan to use a significance level of α = 0.05 to test the claim that p1 = p2, Use the given sample sizes and numbers of successes to find the P-value for the hypothesis test.

7) n1 = 50 n2 = 75

x1 = 20 x2 = 15

A) 0.1201 B) 0.0032 C) 0.0001 D) 0.0146

Use the traditional method writing null and alternative hypothesis to test the given claim. Assume that the samples are independent and that they have been randomly selected

8) Use the given sample data to test the claim that p1 > p2. Use a significance level of 0.01.

n1 = 85 n2 = 90

x1 = 38 x2 = 23

Use the traditional method to test the given hypothesis. Assume that the samples are independent and that they have been randomly selected

9) Seven of 8500 people vaccinated against a certain disease later developed the disease. 18 of 10,000 people vaccinated with a placebo later developed the disease. Test the claim that the vaccine is effective in lowering the incidence of the disease. Use a significance level of 0.02.

10) In a random sample of 300 women, 45% favored stricter gun control legislation. In a random sample of 200 men, 25% favored stricter gun control legislation. Construct a 98% confidence interval for the difference between the population proportions p1 - p2.

A) 0.118 < p1 - p2 < 0.282 B) 0.092 < p1 - p2 < 0.308

C) 0.102 < p1 - p2 < 0.298 D) 0.114 < p1 - p2 < 0.286

Test the indicated claim about the means of two populations. Assume that the two samples are independent simple random samples selected from normally distributed populations. Do not assume that the population standard deviations are equal. Use the traditional method or P-value method as indicated.

11) Two types of flares are tested and their burning times (in minutes) are recorded. The summary statistics are given below.

n = 35 n = 40

= 19.4 min = 15.1 min

s = 1.4 min s = 0.8 min

Use a 0.05 significance level to test the claim that the two samples are from populations with the same mean. Use the traditional method of hypothesis testing.

12) A researcher wishes to determine whether people with high blood pressure can reduce their blood pressure, measured in mm Hg, by following a particular diet. Use a significance level of 0.01 to test the claim that the treatment group is from a population with a smaller mean than the control group. Use the traditional method of hypothesis testing.

n1 = 101 n2 = 105

= 120.5 = 149.3

s1 = 17.4 s2 = 30.2

13) A researcher was interested in comparing the amount of time spent watching television by women and by men. Independent simple random samples of 14 women and 17 men were selected, and each person was asked how many hours he or she had watched television during the previous week. The summary statistics are as follows.

Construct a 99% confidence interval for the difference between the mean amount of time spent watching television for women and the mean amount of time spent watching television for men.

A) -6.04 hrs < μ1 - μ2 < 3.24 hrs B) -5.92 hrs < μ1 - μ2 < 3.12 hrs

C) -6.05 hrs < μ1 - μ2 < 3.25 hrs D) -5.91 hrs < μ1 - μ2 < 3.11 hrs