Question

QUESTION 8 Two surgical procedures are widely used to treat a certain type of cancer. To compare the success rates of the two procedures, random samples of the two types of surgical patients were obtained and the numbers of patients who showed no recurrence of the disease after a 1-year period were recorded. The data are shown in the table. How large a sample would be necessary in order to estimate the difference in the true success rates to within .10 with 95% reliability? n1 = n2 = 65 n1 = n2 = 192 n1 = n2 = 93 n1 = n2 = 47 QUESTION 9 Find the critical value F 0 for a right-tailed test using α = 0.01, degrees of freedom in the and degrees of freedom in the denominator = 20. 3.09 4.94 5.82 25.58

QUESTION 10 Calculate the test statistic F to test the claim that > . Two samples are randomly selected from populations that are normal. The sample statistics are given below. Use α = 0.02. n 1 = 13 n 2 = 12 = 13.328 = 10.626 1.254 0.797 1.120 1.573

Answer 1

Ans:

8)

Margin of error=0.10=1.96*sqrt((0.5*(1-0.5)/n1)+(0.5*(1-0.5)/n2))

n₁=n₂=n

0.10=1.96*sqrt(0.5/n)

sqrt(0.5/n)=0.10/1.96

0.5/n=(0.10/1.96)^2

n=0.5*(1.96/0.10)^2

n=192

Correct option is:

n₁=n₂=192

9)

alpha=0.01

df(numerator)=3

df(denominator)=20

Critical F value=FINV(0.01,3,20)=4.94

10)

F statistic=s₁^2/s₂^2

F statistic=13.328/10.626=1.254