Mock Problems


Statistic Pre – requisite Sample Question

1)      What is the underlying element of all statistical sampling techniques?

 

2)      As a member of the student council at your university, you have been assigned the task of conducting a phone survey of undergraduate students to determine satisfaction with the campus food service. Explain how you would go about selecting a simple random sample?

 

3)      Explain the difference between a stratified random sample and cluster random sample

 

4)      Explain the types of information that can be conveyed by a frequency histogram

 

5)      Why would a histogram contain no gaps between the bars but a bar chat may have gaps?

 

6)      Suppose that you have a data set of 512 observations and the data value range from 36 to 187. What classes would you choose for this data set? Explain why you would choose these values.

 

7)      The AMI Company has two assembly lines in its Kansas City plant. Line A produces an average of 335 units per day with a standard deviation equal to 11 units. Line B produces an average of 145 units per day with a standard deviation equal to 8 units. Based on the information, which line is relatively more consistent?

 

8)      The following sample data reflect electricity bills for ten households in San Diego in March.

 

$118.20 $67.88 $133.40 $88.42 $110.34
$76.90 $144.56 $127.89 $89.34 $129.10

Determine three measures of central tendency for these sample data. Then, based on these measures, explain why you think the sample data are symmetric or skewed.

 

9)      Explain how the empirical rule can be used to help describe data in a population or a sample

 

10)   Until the summer of 2006, the real estate market in Fresno, California, had been booming, with prices skyrocketing. Recently a study showed the sales patterns in Fresno for single-family homes. One chart presented in the commission’s report is reproduced here. It shows the number of homes sold by price range and number of days the home was on the market.

 

 

Days on the Market

Price Range ($000)

1-7

8-30

Over 30

Under $200

125

15

30

$200-$500

200

150

100

$501-$1000

400

525

175

Over $1000

125

140

35

 

Construct and answer three questions from these data using:

a)      Addition rule

b)      The multiplication rule

c)       Conditional probability

 

11)   Explain what is meant by the term mutually exclusive events. Cite an example

 

12)   What is the difference between a discrete random variable and a continuous random variable? Give examples.

 

13)   Explain what the expected value of a discrete random variable measures.