W. Watkins


Last update: 20-Nov-2014






Fall 2014:


Math 103:

Information Sheet:

XYZ Instructions:



Math 340:

Information Sheet:


Homework Assignments

Due Sep 3: Ch 2: 9, 13, 14, 17

Due Sep 8: Ch 2:

       29 Two additional jurors ..

       37 A businesswoman in Philadelphia …

       41 How many different seven-digit …

       55 A study is to be conducted in a hospital …

       59 Five cards are dealt from …

              a. 3 aces and 2 kings

              b. “full house”

       76 A survey of consumers …10% were

Due Sep 15: Ch 2:

       71 If two events A and B are such that P(A)=.5..

       73 Gregor Mendel was a monk…

       75 Cards are dealt, one at a time, …

       85 If A and B are independent events. Show the A and B(bar) …

       90 Suppose that there is a 1 in 50 chance…

       93 In a game, a participant is given three attempt …

Due Sep 22: Ch 2:

       125 A diagnostic test for a disease…

       133 A student answers a multiple-choice examination…

       137 Five identical bowls…

       Ch 3:

       3 A group of four components…

       5 A problem in a test…

       9 In order to verify…


Due Sep 29: Ch 3:

       37 In 2003, the average combined SAT

       39 A complex electronic system

       41 A multiple-choice examination

       53 Tay-Sachs disease

       59 Ten motors are packaged


Due Oct 6: Ch3:

       127 The number of typing errors…

       131 The number of knots…

       187 Consider the following game…

       193 Two assembly lines I and II have the same


OK I got a copy of the 7th edition.  Here’s the assigned homework as I wrote it on the board in class:


Oct 20: Ch 3:

       103 A warehouse contains ten printing machines

       105 In southern California, a growing number

       109 Seed are often treated with fungicides

       115 Suppose that a radio contains six transitors

       119 Cards are dealt … all 4 aces if it is known … at least 3 aces?

Ch 4:

       11 Suppose that Y .. density function f(y)=cy, 0<=y<=2

       15 As a measure of intelligence

       21 If, as in Ex…, Y has density function f(y)=(3/2)y^2+y, 0<=y<=1, find mean and variance of Y


Oct 27 Ch 4:

       21 Same as above

       31 Daily total solar radiation…

       39 If a parachutist lands at a random point…

       51 The cycle time for trucks hauling..

       58 Use Table 4, Appendix 3, to find …. a. P(0<=Z<=1.2), b. …






Ch4:  As a measure of intelligence, mice … f(y)=b/y^2 …

       Suppose that Y has density function f(y)=ky(1-y), 0 <=y<=1.

       A parachutist lands

       A telephone call arrived at a switchboard…

       The cycle time for trucks hauling concrete…

       Use Table 4, Appendix III to find the following…for a standard normal r.v.

a.    P(0<=Z<=1.2)


Find the value of z0 such that P(Z>z0)=.5 

A company that manufacture and bottles apple juice..

The grade point averages of a large population of college students … with mean 2.4 and standard deviation 0.8.  What fraction … grade point average in excess of 3.0?



Exam 2 on Oct 29 will cover 3.5 (geometric), 3.7 (hypergeometric), 3.8 (Poisson), 4.1-4.5.  I will supply formulas for the probability and density functions for these random variables and the Z-table.



Nov 3: Ch 4:

       91 The operator of a pumping station

       93a Historical evidence indicates that times between fatal accidents

       97 A manufacturing plant uses a specific bulk produce.

       104 The lifetime (in hours) Y of an electronic component is a random

              f(y)=(1/100)e^(-y/100), y>0


Nov 10: Ch 5:

       1 Contracts for two construction jobs

       3 Of nine executives in a business firm, four are married,

       5 Refer to Example 5.4. The joint density of Y1, the proportion of the capacity..

              and Y2, the proportion of the capacity

       7 Let Y1 and Y2 have joint probability density function given by

              f(y1,y2)=ky1y2, 0<=y1<=1, 0<=y2<=1

       11 Suppose that Y1 and Y2 are uniformaly distributed over the triangle shade in …


Nov 17: Ch 5:

       16a Let Y1 and Y2 denote the proportions of time (out of one workday) ..

       18 An electronic system has one each of two different types of components in joint operation.

       19 In exercise 5.1, we determined that the joint distribution of Y1, the number of contracts awarded

       26 In Exercise 5.8, we derived the fact that

              f(y1,y2)=4y1y2, )<=y1<=1, 0<=y2<=1

                      =0 else

              is a valid ..

       37 In Exercise 5.18, Y1 and Y2 denoted the lengths of life, in hundreds of hours, for ..types I and II..


Nov 24: Read Section 5.4, Independent Random Variables—especially Theorem 5.4.

Ch5: 51a In exercise 5.7, we considered … f(y1,y2)=e^-(y1+y1), y1>0, y2>0

52 In Exercise 5.8, we derived…

       f(y1,y2), 0<=y1<=1, 0<=y2<=1

61 In Exercise 5.18, … lengths of life, … types I and II …f(y1,y2)=(1/8)y1e^-(y1+y2)/2

73 In Exercise 5.3 …number of married executives …where 0<=y1<=3, 0<=y2<=3, 1<=Y1+y2<=3.

Find the expectednumber of married execs. Among the three selected …

75a Refer … Let …f(y1,y2)=e^-(y1+y2), y1>0, y2>0

76a,c In Exercise 5.8, we … f(y1,y2)=4y1y2, )<=y1<=1, 0<=y2<=1


Exam 3 on Nov 26 will cover sections 4.6 (Exponential distribution only), 5.1, 2, 3, 4, 5.