If the standard deviation of the population is σ, the standard deviation of the sample 읊 where "n" is the number of observations in each sample. means is True False

Test scores for a Statistics class have a mean of 81 with a standard deviation of 4. Test scores for a calculus class had a mean of 75 with a standard deviation of 3.5. Suppose a student gets an 87 on the statistics test andan 86 on the calculus test. Calculate the z-scores for each test. On which test did the student perform better relative to the other students in the class.

When standardizing, the mean becomes 0 and the standard deviation becomes 1. True False

Assume that a nomral distribution has a mean of 22 and a standard deviation of 7. What percentage of the values are in the distribution do we expect to fall between 15 and 22?

Entry to a certain University is determined by a national test. The scores on this test are normally distributed with a mean of 500 and a standard deviation of 100. Tom wants to be admitted to this university and he knows that he must score better than at least 80% of the students who took the test. Tom takes the test and scores 595. Will he be admitted to this university?

True or false. If the standard deviation of a dataset is 0, the mean must also be 0.

Jeremiah earned a score of 530 on Exam A that had a mean of 450 and a standard deviation of 40. He is about to take Exam B that has a mean of 63 and a standard deviation of 20. How well must Jeremiah score on Exam B in order to do equivalently well as he did on Exam A? Assume that scores on each exam are normally distributed.

In a test, the average of the grades is 80 and the standard deviation is 5. John's grade is 70, so his grade is standard deviations the average. 2 below 10 --------- below 70 above equal to

A population has a mean of u=50 and a standard deviation of 0=10. If 3 points were added to every score in the population, what would be the new values for the mean and standard deviation?

Why do deviation scores have to be squared before calculating the standard deviation? Squaring is necessary when calculating inferential statistics. If deviation scores are not squared, then the average distance from the mean will always equal 0. Squaring deviation scores allows for degrees of freedom to be calculated. If deviation scores are not squared, then the interquartile ranges are incalculable.