Question

Question 5 (5 points) Expedia would like to assess the hypothesis that the proportion of United Airline flights that arrive on-time is less than 0.80. A random sample of 110 United Airline flights found that 82 arrived on-time. Expedia would like to set α = 0.02. The p-value for this hypothesis test would be ________.

Question 5 options:

a) 0.0322

b) 0.0448

c) 0.0764

d) 0.0912

Answer 1

Solution :

This is the left tailed test .

The null and alternative hypothesis is

H₀ : p = 0.80

H_a : p < 0.80

$\hat p$  = x / n = 82 / 110 = 0.7455

P₀ = 0.80

1 - P₀ = 1 - 0.80 = 0.20

Test statistic = z

= $\hat p$ - P₀ / [$\sqrt$P_{0 *} (1 - P₀ ) / n]

= 0.7455 -0.80/ [$\sqrt$(0.80 * 0.20) / 110]

Test statistic = z = -1.43

P(z < -1.43)

P-value = 0.0764

correct option is = c