Question

A simple random sample of front-seat occupants involved in car crashes is obtained. Among 2736 occupants not wearing seat belts, 39 were killed. Among 7798 occupants wearing seat belts, 19 were killed. Use a 0.05 significance level to test the claim that seat belts are effective in reducing fatalities. Complete parts (a) through (C) below. a. Test the claim using a hypothesis test. Consider the first sample to be the sample of occupants not wearing seat belts and the second sample to be the sample of occupants wearing seat belts. What are the null and alternative hypotheses for the hypothesis test? O A. Ho: P1 = P2 H:17P2 OB. Ho P12P2 Hy: P1 P2 OC. Ho: P1 P2 H:27+ P2 OD. Ho: P1 = P2 HP1 P2 O E. Ho P1 = P2 Hi P1 P2 OF. Ho: P + P2 Hy-P1 = P2 Identify the test statistic. za (Round to two decimal places as needed.) Identify the P-value P-value = (Round to three decimal places as needed.) What is the conclusion based on the hypothesis test? The P-value is the significance level of a = 0.05, SO the null hypothesis. There sufficient evidence to support the claim that the fatality rate is higher for those not wearing seat belts Click to select your answer(s). ?

Answer 1

Ho: P1 = P2 H: P1 > P2

b = = 39 == 0.0143 2736

Ô2 = x = 7198 = 0.0024

P= X1+X Ni+N2 39+19 2736+7798 0.0055

test statistic value is

PI -P2 p(1-D (1/nı +1/n2) 0.0143 -0.0024 0.0055 - (1 -0.0055) (1/2736 + 1/7798) = 7.187

p value is

P(Z>7.187) = 1-P(Z<=7.187) = 1-1 = 0.000

less than,Reject,is