Question

1. The volume of milk in a jug is a variable which is:   

[A]       qualitative       [B]       quantitative discrete    [C]   quantitative continuous

2. Which of the following is not a measure of variability?

[A]       variance           [B]       range               [C]       median            [D]       standard deviation

3. The upper quartile of a large data set is 52. What percent of the observations are greater than 52?

[A]       63%                 [B]       37%                 [C]       75%                 [D]       25%

4. Scores on the final exam taken by 1200 students have a mound-shaped distribution with mean 72 and standard deviation 9. Approximately what percent of the students scored below 54?

[A]       2.5%                [B]       5%                   [C]       16%                 [D]       95%                

5. The z-score of a an observation equal to 35 from a population with mean 50 and a standard deviation equal to 10 equals:

      [A]       -2.50                [B]       -1.75                [C]       -3.50               [D]       -1.50

Answer 1

1. The volume of milk in a jug is a variable which is:

ans-> c) quantitative continuous

2. The following which is not a measure of variability -

ans-> c) median

3. The percent of the observations are greater than 52 -

ans-> d) 25%

4. mean - (2*standard deviation) = 72 - (2*9) = 54

Using empirical rule,

95% values will lie between ( mean - 2*standard deviation, mean + 2*standard deviation) = (54, 90)

So, (100 - 95) = 5% values lie outside the interval ( mean - 2*standard deviation, mean + 2*standard deviation)

Approximately, percent of the students scored below 54 = (100 - 95)/2 = 2.5

ans-> a) 2.5%

5. The z-score of a an observation equal to 35 from a population with mean 50 and a standard deviation equal to 10 equals

ans-> d) -1.5