Question

A random sample of 260 recent donations at a certain blood bank reveals that 117 were type A blood. Does this suggest that the actual percentage of Type A donations differs from 40%, the percentage of the population having Type A blood? [Answer the questions, where appropriate, using 4 digits after decimal.]

1.What are the appropriate hypotheses to test?
a) H₀: p = 0.4500 against   H_a: p > 0.4500.
b) H₀: p = 0.4500 against   H_a: p < 0.4500.
c) H₀: p = 0.4 against   H_a: p ≠ 0.4.
d) H₀: p = 0.4500 against   H_a: p ≠ 0.4500.
e) H₀: p = 0.4 against   H_a: p > 0.4.
f) H₀: p = 0.4 against   H_a: p < 0.4.

2.The test-statistic formula is:
a) z = \dfracp − 0.4√{0.4 (1−0.4)/260}
b) z = \dfracp − 0.4500√{0.4500 (1−0.4500)/260}
c) z = \dfrac[^(p)] − 0.4√{0.4 (1−0.4)/260}
d) z = \dfrac[^(p)] − 0.4500√{0.4500 (1−0.4500)/260}

3. Rejection region: We reject H₀ at 1% level of significance if:
a) z < −2.341.
b) z < −2.326.
c) |z| > 2.595.
d) |z| > 2.576.
e) z > 2.341.
f) z > 2.326.

4. What is the value of the test-statistic?

A: -7.0006

B: -3.6301

C: -2.6869

D: 0.5193

E: 1.6457

F: 8.1581

5. What is the p-value of the test?

A: 0.0135

B: 0.0499

C: 0.0998

D: 0.6249

E: 0.7672

F: 0.9501

6. For a significance level of 1%, the data would lead to
a) not enough information to reach a decision.
b) not rejection of the null hypothesis.
c) rejection of the null hypothesis.

Answer 1