The mean and median of the marks of a group of 75 students in at test were calculated as 27 and 29 respectively. It was later discovered that two observations were wrongly recorded as 53 and 45 instead of 35 and 55. Examine to what extent the calculated value of the above two measures will be affected by the discovery of the errors.

A psychologist wants to estimate the amount of math anxiety that the population of high school students experience prior to taking their first algebra course. On the first day of class he asks a sample of 36 students to answer the question, “How anxious do you feel when you know you have to do math problems?” They each responded using a 100-point scale with 1 = not at all anxious and 100 = extremely anxious. The mean reported anxiety score for this sample was 58 with a standard deviation of 30 Compute the upper and lower boundaries for this 95% confidence interval.     LB = 66.45, UB - 49.55     LB = 28, UB = 88     LB = -5.00, UB = 5.00     LB = 47.86, UB = 68.15     LB = -10.15, UB = 10.15

Miss Romero noted that the mean scores of a random sample of 15 Grade 8 students who had taken a special test was 80.5. If the standard deviation of the scores was 3.1, and the sample came from an approximately normal population, find the point and interval estimate of the population mean, using 95% confidence.

The sample data here is the cholesterol levels for 10 men diagnosed with high cholesterol. The first row represents levels from 10 men who did not use the drug and the second row from 10 different men who did use the drug. If we want to test the claim that the mean level for all men who use the drug is less than the mean for all men who do not use it, what is the appropriate alternative hypothesis?    The mean cholesterol level of males who take the medicine is higher than the mean cholesterol levels of men who do not take it.       There is a significant difference between males who use the medicine and men who do not use the drug in terms of mean cholesterol levels.       The mean cholesterol level of males who take the medicine is lower than the mean cholesterol levels of men who do not take it.       There is no significant difference between males who use the medicine and men who do not use the drug in terms of mean cholesterol levels.

The mean marks of 100 students were found to be 40. Later on it was discovered that a score of 53 was misread as 83. Find the corrected mean corresponding to the corrected score.

Mariah and Amanda began arguing about who did better on their tests, but they couldn't decide who did better given that they took different tests. Mariah took a test in English and earned a 81, and Amanda took a test in Art History and earned a 61.8. Use the fact that all the students' test grades in the English class had a mean of 75.7 and a standard deviation of 9, and all the students' test grades in Art History had a mean of 60.7 and a standard deviation of 10.3 to answer the following questions.a) Calculate the z-score for Mariah's test grade.z=b) Calculate the z-score for Amanda's test grade.z=c) Which person did relatively better? Mariah Amanda They did equally well.

For item 4 to 6. Table 3.8 shows the heights of a sample of 12 fathers and their oldest adult sons. Find the coefficient of rank correlation in two decimal places. Height of father(inches) 65 63 67 64 68 62 70 66 68 67 69 71 X Height of 68 66 68 65 69 66 68 65 71 67 68 70 son(inches) Y sample answer. 0.15 -0.65

The distribution of heights of adult men is approximately normal with mean 69 inches and standard deviation 2.5 inches. Bob's height has a Z-score of -2.5 when compared to all adult men. In 1-2 sentences, interpret what this Z score tells about how Bob compares to other men in terms of height.

suppose that a category of world-class runners are known to run a marathon (26 miles) in an average of 143 minutes with a standard deviation of 14 minutes. consider 49 of the races. Let x̅ = the average of the 49 races. I need help finding the median of the average running times. if someone could explain how to solve this problem that would be great

Alice was told that her reading test score was one standard deviation below to me if test scores were approximately normal with m= 86 and standard deviation= 4. What was Alice's score?