One Sample Proportion Z Test

USA Today reported that in 1992, 39% of all elementary school children claimed that when they grow up they want to do something to help other people. However, in 1995, 128 of a random sample of 317 of these same children claimed that when they grow up they want to do something to help other people. Does this information indicate that there has been an attitude change either way?

• One-Sample Z Test for a Proportion

• Two-Sample Z Test for the Difference in Proportions

• One-Sample T Test for a Mean

• Two-Sample T Test for the Difference in Means

The manufacturer of a particular brand of microwave popcorn claims that only 2 percent of its kernels of corn fail to pop. A competitor, believing that the actual percentage is larger, tests 2,000 kernels and finds that 44 failed to pop. Do these results provide sufficient evidence to support the competitor's belief?

• One-Sample Z Test for a Proportion

• One-Sample T Test for a Mean

• Two-Sample Z Test for a Proportion

• Matched-Pairs T Test for a Mean

Which are necessary conditions to perform a significance test for a population proportion?

• Normal distribution of the population

• SRS from the population

• A sample size of at least 15

• A sample size that is less than 10% of the population size

Given an SRS of 20 math scores. Do we have reason to believe that the true proportion of students who score below 600 in math is not 50%?

• One-Proportion z-Test

• One-Sample t-Test

• One-Sample t-Test on Matched Pairs

• Two-Proportion z-Test

• A

• B

• C

• D

• E

A manufacturer has a set limit that the proportion of defective items is not to be over 18%. The buyer thinks the proportions of defective items exceeds the limit. The buyer take a random sample of 90 items and finds that 19 of them are defective.   The z-score is closest to:

• 0.25

• 0.61

• -0.25

• -0.77

According to Pew Research, about 63% of American adults are working from home by choice. Suppose you survey a random sample of 600 American adults and ask if they are working from home by choice. What proportion of your sample would you expect to say yes? ​ Compute the standard error for your sample proportion. ​ Calculate the z-score for a sample proportion of 58%. ​ Would it be surprising to obtain a sample proportion of 58%? ​ ​

• 63%

• 0.0197

• -2.54

• Yes, it is outside of 2 SE

• No, it is within reason

• 1.971

• 37%

• 50%

According to the Center for Disease Control, 93% of children entering kindergarten in the U.S. are vaccinated.
Find the z-score associated with a sample of 180 children in which 162 have been vaccinated.

• -1.34

• 1.34

• .0901

• .9099

According to Pew Research, about 63% of American adults are working from home by choice. Suppose you survey a random sample of 600 American adults and ask if they are working from home by choice. What proportion of your sample would you expect to say yes? ​ Compute the standard error for your sample proportion. ​ Calculate the z-score for a sample proportion of 58%. ​ Would it be surprising to obtain a sample proportion of 58%? ​

• 63%

• 0.0197

• -2.54

• Yes, it is outside of 2 SE

• No, it is within reason

• 1.971

• 37%

• 50%

Given an SRS of 30 math scores, what is an estimate of the true proportion of students in this population that score over 650 in math?

• One-Proprtion z-Test

• One-Proportion z-Interval

• One-Sample t-Interval

• One-Sample t-Interal on Matched Pairs