Are you smarter than a second grader? A random sample of 70 second graders in a certain school district are given a standardized mathematics skills test. The sample mean score is =x55. Assume the standard deviation of test scores is =σ21. The nationwide average score on this test is 50. The school superintendent wants to know whether the second graders in her school district have greater math skills than the nationwide average. Use the =α0.05 level of significance and the P-value method with the TI-84 Plus calculator.Part: 0 / 50 of 5 Parts CompletePart 1 of 5(a) State the appropriate null and alternate hypotheses.:H0  :H1  This hypothesis test is a ▼(Choose one) test.

A study conducted by a technology company showed that the mean time spent per day browsing the video streaming service Netflix for something to watch was 20.6 minutes. Assume the standard deviation is =σ8. Suppose a simple random sample of 102 visits taken this year has a sample mean of =x19.6 minutes. A social scientist is interested to know whether the mean time browsing Netflix has decreased. Use the =α0.05 level of significance and the P-value method with the TI-84 Plus calculator.Part: 0 / 50 of 5 Parts CompletePart 1 of 5(a) State the appropriate null and alternate hypotheses.H0: 20.6H1: 20.6

Question 10Drs. Melnyk and Ahmed conducted a study in which 400 participants completed a 50-point test about their knowledge of statistics. The mean score was 40 with a standard deviation of 5. These results approximated a normal distribution, which means that the probability of a score between 0 and 1 standard deviations was about 34.1%, between 1 and 2 standard deviations was about 13.6%, and above 2 standard deviations was about 2.3%. If Ashley’s score on this test was 50, what percentage of students are below Ashley’s score? 1 point97.7%13.6%99.8%47.7%

The standard deviation of test scores on a certain achievement test is 11.3. A random sample of 50 scores on this test had a mean of 75.9. Based on this sample, find a 95% confidence interval for the true mean of all scores. Then give its lower limit and upper limit.Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas.)Lower limit: Upper limit:

A student in a statistics class needs to do a project and decides to find out if the average high school GPA of students in a statistics course at her university is higher than the average high school GPA for their university. The university’s average high school GPA of enrolled students in their year was 4.41.She emails a survey to all of her friends that are taking statistics and asks them what their high school GPA is. Her sample contains 18 responses. She chooses a 5% level of significance. From her data, she calculates a t-test statistic of approximately 1.41 with a p-value of about 0.08. What can she conclude? The data is not statistically significant. In other words, the data do not provide enough evidence to conclude that the mean GPA of students taking statistics at her university is higher than 4.41. The data is statistically significant. In other words, the data do provide enough evidence to conclude that the mean GPA of students taking statistics at her university is higher than 4.41. Nothing. The conditions for use of a t-test are not met. She cannot trust that the p-value is accurate for this reason.

Question 2381 random elementary schools were asked for their average exam scores (sample mean = 535, sample standard deviation = 7). Calculate the 98% confidence interval.1 point(528.00, 542.00)(533.15, 536.85)Not possible to calculate based on this information.(533.41, 536.59)