On a multiple choice test with 10 questions, each question has four possible answers, one of which is correct. For students who guess at all answers, find the standard deviation for the number of correct answers.

Find the z-score that corresponds to the 63rd percentile

Which test was better?. Gina took a midterm in her math class and her biology class. After she gets her grades for those midterms, she wonders if she did better on the math midterm or the biology midterm. For the math test, she received 47 points where the mean was 39 and the standard deviation was 13. Calculate the z-score for the math test for Gina. Be sure to round to 2 decimal places. Answer:

CO LO Translate Mikayla and April began arguing about who did better on their tests, but they couldn't decide who did better given that they took different tests. Mikayla took a test in Science and earned a 78.6, and April took a test in English and earned a 61.3. Use the fact that all the students' test grades in the Science class had a mean of 75.6 and a standard deviation of 11.8, and all the students' test grades in English had a mean of 65.3 and a standard deviation of 9.6 to answer the following questions. a) Calculate the z-score for Mikayla's test grade. [Round your answer to two decimal places.] 三2 b) Calculate the z-score for April's test grade. [Round your answer to two decimal places,] 三2 c) Which person did relatively better? Mikayla O April O They did equally well. Submit Question 52°F Clou +56 五。 Or

A professor grades students on three tests, four quizzes, and a final examination. Each test counts as two quizzes and the final examination counts as two tests. Sara has test scores of 95, 70, and 86. Sara's quiz scores are 91, 66, 76, and 85. Her final examination score is 95. Use the weighted mean formula to find Sara's average for the course. (Round your answer to one decimal place.)

Willie has an average (mean) of 83.2 on the first five exams. What is the least he can score in order to have an average of 85 for all six exams?

For standard deviation, the x-x or the y-y, which numbers do you use?

Please solve for D,E, and F

Allie has 5 exam scores 98, 94, 84, 95 and 95 in math class. What score does she need on the final to have a mean grade of 90?  Round answer two decimal places if necessary. All exams have a maximum of 100 points.

A recent Nielsen analysis found that the typical U.S. smartphone user is spending an average of 220 minutes per day using apps. We speculate that the average time spent using apps for Generation X smartphone users (aged 41-56 years) is less than the national average. The hypotheses are Ho: H = 220 minutes versus Ha: µ < 220 minutes. Summary results from R are provided. Summary Statistics Std. Dev (s) Mean Sample Size (n) 205 minutes 63.25 minutes 31