1 Suppose that you take an exam with 433 possible points and are told that the mean score is 284 and that the standard deviation is 27.

You are also told that you got 378. Did you do well on the? exam? Explain your answer.

Determine the? z-score and interpret this score.

A score of 378 has a? z-score of _____ This is______standard deviation____ (below or above) the mean for this exam. The____

(Chebyshev's rule, or three-standard-deviation rule, or empirical rule) states that approximately? 99.7% of the observations lie within_____

(five, one, two, four, or three) standard deviations of the mean. Since this score is___ (less than two, more than three, or less than three) standard deviations____ (below or above) the? mean, this is a___(good or bad) score.??

?(Round to two decimal places as? needed.)

2

In a study of the effects of radiation on amphibian embryos, the time it took a sample of seven different species of frogs' and toads' eggs to hatch was recorded. The following table shows the times to hatch, in days. Complete parts (a) through (c) below. 7 9 14 7 6 6 14 D a. Find the mean. The mean is E. (Type an integer or decimal rounded to one decimal place as needed.) b. Find the median. The median is (Type an integer or decimal rounded to one decimal place as needed.) c. Find the mode(s). Select the correct choice below and, if necessary, ll in the answer box within your choice. '3._:3' A- The mode(s) is(are) (Use a comma to separate answers as needed.) (1- B. There is no mode. Explain the difference between the quantities ( _x; ) and _X; . Construct an example to show that, in general, those two quantities are unequal. . . . Choose the statement that best states the difference between the two expressions. O A. The expression Ex; represents the square of the sum of the data, whereas (Ex; ) represents the sum of the squares of the data. O B. The expression (Ex; ) represents the square of the sum of the data, whereas _x; represents the sum of the squares of the data. O C. The expression (_x; ) - represents the square of the sum of the squares of the data, whereas _x; represents the sum of the squares of the data. O D. There is no difference between the expression ( _x; ) and the expression Ex; 2. Use the table to the right to find the values of each expression. Consider three observations on x as presented in column 1 of the table, and consider each observation's square, as presented in column 2. ( Ex; ) 2 = X N X S 9 25 Ex, 2 = Therefore, (Ex; ) 2 Ex; 2