MATH302 Week 6 Knowledge Check Homework Practice QuestionsWinter Session
Course : American Public
Contributed : Catherine
- $15.00
- Question: An adviser is testing out a new online learning module for a placement test. They wish to test the claim that on average the new online learning module increased placement scores at a significance level of α = 0.05. For the context of this problem, μD=μnew–μold where the first data set represents the new test scores and the second data set represents old test scores. Assume the population is normally distributed.
- Question: A researcher is testing reaction times between the dominant and non-dominant hand. They randomly start with each hand for 20 subjects and their reaction times in milliseconds are recorded. Test to see if the reaction time is faster for the dominant hand using a 5% level of significance. The hypotheses are:
- Question: Two competing toothpaste brands both claim to produce the best toothpaste for whitening. A dentist randomly samples 48 patients that use Brand A (Group 1) and finds 30 of them are satisfied with the whitening results of the toothpaste. She then randomly samples 45 patients that use Brand B (Group 2) and finds 33 of them are satisfied with the whitening results of the toothpaste. Construct a 99% confidence interval for the difference in proportions and use it to decide if there is a significant difference in the satisfaction level of patients.
- Question: In a 2-sample z-test for two proportions, you find the following: Find the test statistic you will use while executing this test.
- Question: Find the test statistic you will use while executing this test.
- Question: In an article appearing in Today's Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean number of calories per serving to be 78 with a sample standard deviation of 7.
- Question: Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5% level of significance.
- Question: Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5% level of significance.
- Question: The alternative hypothesis is also known as the:
- Question: Suppose that the mean time for a certain car to go from 0 to 60 miles per hour was 7.7 seconds. Suppose that you want to test the claim that the average time to accelerate from 0 to 60 miles per hour is longer than 7.7 seconds. What would you use for the alternative hypothesis?
- Question: You are testing the claim that the mean GPA of night students is different from the mean GPA of day students. You sample 30 night students, and the sample mean GPA is 2.35 with a standard deviation of 0.46. You sample 25 day students, and the sample mean GPA is 2.58 with a standard deviation of 0.47. Test the claim using a 5% level of significance. Assume the sample standard deviations are unequal and that GPAs are normally distributed.
- Question: You are testing the claim that the mean GPA of night students is different from the mean GPA of day students. You sample 30 night students, and the sample mean GPA is 2.35 with a standard deviation of 0.46. You sample 25 day students, and the sample mean GPA is 2.58 with a standard deviation of 0.47. Test the claim using a 5% level of significance. Assume the sample standard deviations are unequal and that GPAs are normally distributed.
- Question: You are testing the claim that the mean GPA of night students is less than the mean GPA of day students. You sample 30 night students and 30 day students. Test the claim using a 10% level of significance. Assume the population standard deviations are unequal. Find the p-value. Round answer to 2 decimal places. Make sure you include the 0 in front of the decimal.
- Question: In a survey of 1000 high school students in Oregon, the average SAT score for 500 students who chose to go out of state for college (Group 1) was 1225 and the average SAT score for 500 students who chose to stay in state for college (Group 2) was 1130. The population standard deviation for students who choose to go out of state is 95 and the population standard deviation for students who choose to stay in state is 103. Find a 95% confidence interval and decide if the SAT scores between the two groups is significantly different. Confidence Interval (round to 4 decimal places):
- Question: In a survey of 100 U.S. residents with a high school diploma as their highest educational degree (Group 1) had an average yearly income was $35,621. Another 120 U.S. residents with a GED (Group 2) had an average yearly income of $34,498. The population standard deviation for both populations is known to be $4,150. At a 0.01 level of significance, can it be concluded that U.S. residents with a high school diploma make significantly more than those with a GED?
- Question: Which of the following is a requirement that must first be satisfied before running a z-test for the difference between two means?
- Question: In a random sample of 50 Americans five years ago (Group 1), the average credit card debt was $5,779. In a random sample of 50 Americans in the present day (Group 2), the average credit card debt is $6,499, Let the population standard deviation be $1,152 five years ago, and let the current population standard deviation be $1,634. Using a 0.01 level of significance, test if there is a difference in credit card debt today versus five years ago. What is the p-value? Make sure you put the 0 in front of the decimal.
- Question: Which of the following symbols represents power ?
- Question: The plant-breeding department at a major university developed a new hybrid boysenberry plant called Stumptown Berry. Based on research data, the claim is made that from the time shoots are planted 90 days on average are required to obtain the first berry. A corporation that is interested in marketing the product, tests 60 shoots by planting them and recording the number of days before each plant produces its first berry. The sample mean is 92.3 days. The corporation will not market the product if the mean number of days is more than the 90 days claimed.
- Question: A student is interested in becoming an actuary. They know that becoming an actuary takes a lot of schooling and will have to take out student loans. They want to make sure the starting salary will be higher than $55,000/year. They randomly sample 30 starting salaries for actuaries and find a p-value of 0.0392.
