In the 1950's only about 40% of high school graduates went on to college. Has the percentage increased?
Give the Null and Alternative Hypotheses.
Use the 'keyboard' icon to enter your information, use subscripts, use '0' for naught, and use 'A' for the alternative.
Use no spaces except after the comma.
Ex.
Use two places past the decimal point.
4 points
4
Question 2
2.
20% of cars of a certain model have needed costly transmission work after being driven between 50,000 and 100,000 miles. The manufacturer hopes that a redesign of a transmission component has solved the problem.
Give the Null and Alternative Hypotheses.
Use the 'keyboard' icon to enter your information.
Use subscripts, use '0' for naught, and use 'A' for the alternative.
Use no spaces except after the comma.
Ex.
Use two places past the decimal point.
4 points
4
Question 3
3.
We field-test a new-flavor soft drink, planning to market it only if we are sure that over 60% of the people like the flavor.
Give the Null and Alternative Hypotheses.
Use the 'keyboard' icon to enter your information.
Use subscripts, use '0' for naught, and use 'A' for the alternative.
Use no spaces except after the comma.
Ex.
Use two places past the decimal point.
4 points
4
Question 4
4.
Only about 20% of people who try to quit smoking succeed. Sellers of a motivational tape claim that listening to the recorded messages can help people quit.
Give the Null and Alternative Hypotheses.
Use the 'keyboard' icon to enter your information.
Use subscripts, use '0' for naught, and use 'A' for the alternative.
Use no spaces except after the comma.
Ex.
Use two places past the decimal point.
4 points
4
Question 5
5.
A governor is concerned about the percentage of state residents who express disapproval of his job performance.
The governor's political committee pays for a series of TV ads, hoping they can lower the governor's 'negative' ratiings to below 30% of respondents.
Results from a poll after the TV ads showed a z-score of -2.37.
Can the governor conclude that the public approval of his job performance has improved?
4 points
4
Question 6
6.
To test the fairness of a coin Westin tossed it many times.
He got heads more than half the time, the z-score for his results was z=0.73.
Can Westin conclude the coin is fair?
4 points
4
Question 7
7.
Some people are concerned that new tougher standards and high-stakes tests have driven up the high school drop-out rate. The National Center for Education Statistics reported that the high school dropout rate for the year 2004 was 10.3%.
One school district whose dropout rate has always been very close to the national average reports that 210 of their 1782 hgh school students dropped out last year.
Is this evidence that their dropout rate may be increasing?
Write the null and alternative hypotheses.
Use the 'keyboard' icon to enter your information.
Use subscripts, use '0' for naught, and use 'A' for the alternative.
Use no spaces except after the comma.
Ex.
Use three places past the decimal point.
4 points
4
Question 8
8.
Some people are concerned that new tougher standards and high-stakes tests have driven up the high school drop-out rate.
The National Center for Education Statistics reported that the high school dropout rate for the year 2004 was 10.3%.
One school district whose dropout rate has always been very close to the national average reports that 210 of their 1782 high school students dropped out last year.
Is this evidence that their dropout rate may be increasing? Calculate the z-score to answer this question:
1st calculate the sample Standard Deviation, use the population proportion, round to three places past decimal.
2nd calculate the sample proportion, round to three places past decimal, see bolded info above re. sample data.
3rd calculate the z-score.
Use three places past the decimal point in your calculations.
4 points
4
Question 9
9.
Some people are concerned that new tougher standards and high-stakes tests have driven up the high school drop-out rate. The National Center for Education Statistics reported that the high school dropout rate for the year 2004 was 10.3%.
One school district whose dropout rate has always been very close to the national average reports that 210 of their 1782 hgh school students dropped out last year.
Is this evidence that their dropout rate may be increasing?
Using your answer to #8, what can you conclude?
4 points
4
Question 10
10.
During the 2013 football season, the home team won 153 of the 256 regular-season National Football League games. Is this strong evidence of a home field advantage in professional football?
Give the null and alternative hypotheses.
Use the 'keyboard' icon to enter your information.
Use subscripts, use '0' for naught, and use 'A' for the alternative.
Use no spaces except after the comma.
Ex.
Use two places past the decimal.
Hint: What % would indicate an even possibility?
4 points
4
Question 11
11.
During the 2013 football season, the home team won 153 of the 256 regular-season National Football League games.
Is this strong evidence of a home field advantage in professional football? You will need to calculate the z-score.
Hint: if it made no difference if the team was home vs. away, what would the % be?
1st calculate the sample Standard Deviation.
2nd calculate the sample proportion.
3rd calculate the z-score.
Round to three places past the decimal point in your calculations.
4 points
4
Question 12
12.
During the 2013 football season, the home team won 153 of the 256 regular-season National Football League games.
Is this strong evidence of a home field advantage in professional football?