Solucionario de probabilidad

Solutions Manual
to accompany

STATISTICS FOR ENGINEERS AND SCIENTISTS
by

William Navidi

Table of Contents

Chapter 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Chapter 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Chapter 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Chapter 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 Chapter 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 115 Chapter 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 Chapter 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168 Chapter 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . 190 Chapter 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 Chapter 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229

SECTION 1.1

1

Chapter 1 Section 1.1
1. (a) The population consists of all the bolts in the shipment. Itis tangible. (b) The population consists of all measurements that could be made on that resistor with that ohmmeter. It is conceptual. (c) The population consists of all residents of the town. It is tangible. (d) The population consists of all welds that could be made by that process. It is conceptual. (e) The population consists of all parts manufactured that day. It is tangible.

3. (a) False(b) True

5. (a) No. What is important is the population proportion of defectives; the sample proportion is only an approximation. The population proportion for the new process may in fact be greater or less than that of the old process. (b) No. The population proportion for the new process may be 0.10 or more, even though the sample proportion was only 0.09. (c) Finding 2 defective bottles inthe sample.

7.

A good knowledge of the process that generated the data.

2

CHAPTER 1

Section 1.2
1. False

3.

No. In the sample 1, 2, 4 the mean is 7/3, which does not appear at all.

5.

The sample size can be any odd number.

7.

Yes. If all the numbers in the list are the same, the standard deviation will equal 0.

9.

The mean and standard deviation bothincrease by 5%.

13. (a) All would be multiplied by 2.54.

(b) Not exactly the same, because the measurements would be a little different the second time.

15. (a) The sample size is n 16. The tertiles have cutpoints 1 3 17 5 67 and 2 3 17 11 33. The first tertile is therefore the average of the sample values in positions 5 and 6, which is 44 46 2 45. The second tertile is the average of the samplevalues in positions 11 and 12, which is 76 79 2 77 5.
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(b) The sample size is n 16. The quintiles have cutpoints i 5 17 for i 1 2 3 4. The quintiles are therefore the averages of the sample values in positions 3 and 4, in positions 6 and 7, in positions 10 and 11, and in positions 13 and 14. The quintiles are therefore 23 41 2 32, 46 492 47 5, 74 76 2 75, and 82 89 2 85 5.
¡ £ ©¥ ¢ ¤ ¨  ¡  £ ¥  ¡ ¢ ¤ ¥ ¤ ¦¥ ¡ £ ¤ £ ¥ ¢ ¤ ¡ ¨ ¡ £ ¥ ¢ ¤

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11.

The total number of points scored in the class of 30 students is 30 72 2160. The total number of points scored in the class of 40 students is 40 79 3160. The total number of points scored in both classes combined is 2160 3160 5320. There are 30 40 70 students in both...