Question

In a test of the effectiveness of prodaf, 40 out of 45 subjects treated with prodaf developed a cold. 88 of 103 subjects treated with a placebo developed a cold. Use a 0.05 significance level to test the claim that prodaf has an effect on  the likelihood of developing a cold.

Critical Values: z0.005 = 2.575, z0.01 = 2.325, z0.025 = 1.96, z0.05 = 1.645

When d.f.=6: t0.005 = 3.707, t0.01 = 3.143, t0.025 = 2.447, t0.05 = 1.943

When d.f.=9: t0.005 = 3.250, t0.01 = 2.821, t0.025 = 2.262, t0.05 = 1.833

When d.f.=44: t0.005 = 2.690, t0.01 = 2.412, t0.025 = 2.014, t0.05 = 1.679

When d.f.=100: t0.005 = 2.625, t0.01 = 2.364, t0.025 = 1.984, t0.05 = 1.660

Answer 1