1 Sample Z Test for Proportions

Front

Write the appropriate hypotheses for the drying procedure that currently produces cracks in 16% of boards. Options: Ho: p = 0.16, Ha: p = 0.16; Ho: p = 0.16, Ha: p ≠ 0.16; Ho: p = 0.16, Ha: p > 0.16; Ho: p = 0.16, Ha: p < 0.16

Back

Ho: p = 0.16
Ha: p < 0.16

Front

A Gallup poll report revealed that 72% of teens said they rarely or never argue with their friends. Yvonne wonders if this result is true for her school. She surveys a random sample of 150 students and 64% of them say they rarely or never argue with friends. She uses the data to perform a test of Ho: p = 0.72 versus Ha: p=/= 0.72. The test yields a p-value of 0.0291. What conclusion would you make for a significance level of 5%?

Back

Since our p-value of 0.0291 is less than 5%, we reject the null hypothesis. We have convincing evidence that the proportion of teens in her school who rarely or never argue with their friends is different from 0.72.

Front

In a random of 850 city high school students, 768 said they had access to the internet during school hours. 308 of 355 rural high school students said they had access. What is the p-value for a significance test to determine if these data provide evidence that the proportion of high school students in city areas who have internet access is different than those who go to rural schools?

Back

0.066

Front

What is the correct interpretation of the p-value in the context of a nutritionist's claim that U.S. children drink an average of less than 2 glasses of milk per day, with a p-value of 0.0015?

Back

About 0.15% of all samples would produce a test statistics at least as extreme as ours if the null hypothesis is true.

Front

A significance test was performed to test the null hypothesis H₀ : p = 0.5 versus the alternative H_a: p > 0.5. The test statistic is z = 1.40. Which of the following is closest to the P-value for this test? Options: 0.0808, 0.1492, 0.1616, 0.2984, 0.9192

Back

0.0808

Front

Which of the following shows a right-tailed test? Options: Ha: p < 15, H₀: p < 15, Ha: p > 15, H₀: p > 15

Back

Ha: p > 15

Front

A mayor wants to know if the percentage of city residents who express approval of his job performance has changed since last election. What are the correct null and alternative hypotheses if p1 is the previous approval rating and p2 is the current approval rating?

Back

Ho: p₁ = p₂
Ha: p₁ ≠ p₂

Front

Write the null and alternative hypotheses for the situation where only 0.5% of the US population has run a marathon, but running is becoming more popular among young people.

Back

Ho: p = 0.005
Ha: p > 0.005