Question

Ten years ago 55% of a country's families owned stocks or stock funds. Sample data collected by an investment company indicated that the percentage is currently 47%. Assume the investment company sampled 300 of the country's families to estimate that the percent owning stocks or stock funds is currently 47%. What is the p-value for your hypothesis test? Find the value of the test statistic. (Round your answer to two decimal places.) Find the p-value. (Round your answer to four decimal places.) p-value =

Answer 1

Solution :

This is the two tailed test .

The null and alternative hypothesis is

H₀ : p = 0.55

H_a : p 0.55

n = 300

= 0.47

P₀ = 0.55

1 - P₀ = 1 - 0.55 = 0.45

z = - P₀ / [P_{0 *} (1 - P₀ ) / n]

= 0.47 - 0.55 / [(0.55 * 0.45) / 300]

= -2.79

Test statistic = -2.79

P(z < -2.79) = 0.0026

P-value = 2 * 0.0026 = 0.0052