10.3

1.

  1. 2.602

  2. -1.729

  3. +/-2.179

2.

  1. t.1=1.321.

  2. -2.426.

  3. +/- 2.738

3.

  1. -1.379

  2. -1.714

  3. Skip this problem.

  4. There is not enough evidence to reject the null hypothesis because it is a left-tailed test and the test statistic is greater than the critical value(-1.379 > -1.714)

4.

  1. 2.67

  2. 1.318

  3. Skip this problem.

  4. There is not enough evidence to reject the null hypothesis because it is a right-tailed test and the test statistic is greater than the critical value(2.67 > 1.318)

5.

  1. 2.502

  2. -2.819 , 2.819

  3. Skip this problem.

  4. there is not sufficient evidence to reject the null hypothesis, since the test statistic is between the critical values (-2.189 < 2.502< 2.819)

  5. Lower bound : 99.39 the upper bound is 110.21 the 99% confidence interval include 100 we do not reject the statement in the null hypothesis

11.

Ho: $67

Ha: >$67

  1. there is a ,02 probability of obtaining a sample mean $73 or higher from a population whose mean is $67 so 100 simple random samples with an n at 40 then the population mean is 67 and we would expect 2 of these samples to have a sample mean of $73

  2. because the pa value is low p value =.02 < .05 we reject te statement in the null hypothesis there is sufficient evidence to conclude that the mean dollar amount withdrawn from a payease atm is more than the mean amount from a standard atm

13.

Ho: 22

Ha: >22

  1. The sample is random, larger than 30 and small compared to the population.

  2. t0 (2.176) is greater than t-alpha (1.660) so the null hypothesis is rejected

  3. There’s sufficient evidence to conclude that the mean ACT score is greater than 22 for the students who complete the core curriculum. 15.

Test statistic = t0 = -4.533 > -t0.01 = -2.718,

Reject the null, there is sufficient evidence to conclude that the mean hippocampal volume in alcoholic adolescents is less than the normal volume of 9.02 cm3.

17.

t= 0.813 < t0.05 = 1.685.

Do not reject the hull, there is no sufficient evidence to conclude that the mean FICO score of high income individuals is greater than that of the general population.

19.

LB is 35.44 UB is 42.36. These are the bounds for the 95% confidence interval.

Do not reject the null because 40.7 is included in the interval. there is no sufficient evidence to conclud that the mean age of death row inmates has change since 2002.

10.4

1.

  1. 28.869

  2. 14.041

  3. 45.722, 16.047

3.

  1. 20.496

  2. 13.091

  3. Skip this problem

  4. Do not reject the null hypothesis, because x^2 0 > x^2 0.95

13.

Note. The sample standard deviation of the data shown is.\(15.205043\). You will have to knit this to see the number though.

x20=6.422 greater than 3.325.

do not reject the null, there is no sufficient evidence to conclude that the standard deviation of weight times is less than 18.0.

15.

x20=15.639 less than 15.659.

reject the null, there is sufficient evidence to conclude that Allen Iverson is more consistent than other shooting guards in the NBA.