# mathematics

- N= pop size = 3000, n= sample size = 50 , use
**multiple labeling**. .

The random-number table is presented as the following:

21074 41745 56965 48771 13205 38634 09453 77892 43107 86543 ……

Who is the fifth member in the sample? ________ Obviously, we are looking for the original label.

2. In this scheme, reject all groups of numbers on the random number table greater than _______

3. Suppose we wanted a sample of exactly 5 out of the population of 3000 by using 1 in k Systematic Sampling. What should the value of k be?

4. With systematic sampling as described in the problem above, what is the probability that the last member in the population, i.e. #3000 would be present in the sample?

5. True or False? If false, please change the statement to make it a true statement.

- Inferential statistics uses sample statistics to estimate population parameters.

- The bar graph is used for categorical data, whereas the histogram is used for numerical data

- The class marks in a histogram are the midpoints of the bars of the histogram,

- DeMorgan’s law states the following: P(A or B)’ = P(A’ and B’)

- If two events are mutually exclusive then they must be independent.

- A stratified sample ensures that the sample is representative of all strata

- With cluster sampling, the best results occur when elements within clusters are internally homogeneous

- With stratified sampling, the best survey results occur when elements within strata are internally homogeneous.

- Calendar times and clock times are ratio scale.

- The bar graph is used for categorical data, and depicts all the parts of a whole.

6. The probability that a student prefers lifting weights to doing aerobic exercise is .21. What is the probability that of two students randomly chosen, at least one prefers weights?

7. A population is made up of 22 males and 21 females. How many ways are there to choose a sample made up of 5 males and 4 females? What type of sampling was used?

8. The sampling technique where a few naturally occurring groups are randomly chosen from all possible groups in the population, and then all subjects belonging to the chosen groups are sampled is known as sampling. Differences between is ______________differences within is _______________.

9. P(A) = .2, P(B) = .3, P(A and B) = .12, then, =

- For 2 events A and B, where P(A) = .5, P(B) = .1, If P(A/B)= .1, find
**P( A and B),****P(A U B), P(B/A)**

- If A and B are independent, find
**P(A ∩ B) and P(A / ) and P(A U B).**P(A) = .7, P(B) = .1

12. Find P(N or P) = P(Z and Pa) = P((Pa or N)/S) =,P(not N , given S)=

. | S | P | Z | Total |

F | 20 | 37 | 23 | |

Pa | 15 | 12 | 23 | |

N | 70 | 66 | 54 | |

Total |

13. P(A UB)=.3 with P(A) = .1 and P(B) = .2, Find:

**P(A ∩ B) =****P(A U B)= ****P(A ****∩ ) = **

14. Make sure you can distinguish between the following scales. Give 2 examples of each.

a. Interval: b. Ratio

c. Nominal: d. Ordinal:.

15. Find P(D) =, P(B/C)=, P(C ∩ A)=, Find P(D/B) =

Name: ___________________________ID#_________________AMS ______Your TA_________________

Answers

- 4

- 50

- 600

- 1/600

- __________ __________ __________ __________ __________

__________ __________ __________ __________ __________

- __________

- __________ _______________________

- _________________ _________________ ________________

- __________

- _________________ _________________ ________________

- _________________ _________________ ________________

- ______________ _______________ _______________ _____________
- ______________ _______________ _______________ _____________ ______________

- Interval______________________________________________________________________________

Ratio

Nominal

Ordinal