Two thousand numbers are selected randomly; 960 were even ...

[tingc95]

Two thousand numbers are selected randomly; 960 were even numbers.
 a. State the hypotheses to determine whether the proportion of odd numbers is significantly different from 50.
  b. Compute the test statistic.
  c. At 90 confidence using the p-value approach, test the hypotheses.

Question 2

A law enforcement agent believes that at least 88 of the drivers stopped on Saturday nights for speeding are under the influence of alcohol. A sample of 66 drivers who were stopped for speeding on a Saturday night was taken. Eighty percent of the drivers in the sample were under the influence of alcohol.
 a. State the null and alternative hypotheses.
  b. Compute the test statistic.
  c. Using the p-value approach, test the hypotheses at the .05 level of significance.

[pami445]

Answer to Question 1

a. H0: P = 0.5
Ha: P  0.5
b. Z = 1.79
c. p-value = .0734 < 0.10; reject H0

Answer to Question 2

a. H0: P  0.88
Ha: P < 0.88
b. Z = -2
c. p-value = 0.0228 < 0.05; reject H0