Question

A newspaper published an article about a study in which researchers subjected laboratory gloves to stress. Among 260 vinyl​ gloves, 58​% leaked viruses. Among 260 latex​ gloves, 8​% leaked viruses. Using the accompanying display of the technology​ results, and using a 0.10 significance​ level, test the claim that vinyl gloves have a greater virus leak rate than latex gloves. Let vinyl gloves be population 1.

Identify: null, alternative hypothesis, test statistic, and P-value.

Answer 1

Explanation:

pop 1 n₁ = 260, p₁ = 58% = 0.58

pop 2 n₂ = 260, p₂ = 8% = 0.08

Null hypothesis: p₁ ≤ p₂

Alternative hypothesis: p₁ > p₂

The test statistic : p₁-p₂ / √{p-sample (1 - p-sample) (1/n₁ + 1/n₂)}

where p-sample is sample proportion = p₁n₁ +p₂n₂ / n₁+n₂

Thus, p-sample = 0.58x260 +0.08x260 / 260+260 =150.8+20.8 / 520 = 171.6 / 520 = 0.33.

Thus, the test statistic is (0.58 - 0.08) / √[0.33 (1-0.33) (0.0038+0.0038)

= 0.5 / √[0.33(0.67) (0.0076)

= 0.5 / √0.00168036

= 0.5 / 0.04099

= 12.20

P = P(Z>12.20) = 1-P(Z≤12.20) at a significance level of 0.1= the p-value is less than the hypothesized thus, we have sufficient evidence to reject the null hypothesis and concluding that vinyl gloves have a greater virus leak than latex gloves.