Math 3339
Homework 3 (Chapter 4)
Name:__________________________________ PeopleSoft ID:_______________
Instructions:
• Homework will NOT be accepted through email or in person. Homework must be submitted through
CANVAS BEFORE the deadline.
• Write in black ink or dark pencil or type your solutions in the space provided. You must show all
work for full credit.
• Total possible points: 100
1. Determine whether or not the following table is a valid probability distribution of a discrete random
variable. Explain why or why not.
a)
x 0 1 2 3
P(x) -0.2 0.1 0.6 0.5
b)
x -1 2 3 10
P(x) 0.2 0.1 0.3 0.5
c)
x 15 16 17 18
P(x) 0.27 0.28 0.32 0.13
a
Probability And Statistics for Engineers And Scientists, Hayter, A. (2007), Chapter 3
, a
2. You and a friend play a game where you each toss a balanced coin. If the upper faces on the coins are
both tails, you win $1; if the faces are both heads, you win $5; if the coins do not match, you lost $1
(or win (-$1)). Given a single play of this game, use X to denote your winnings, find
a) the probability distribution of X.
b) the mean value of X.
c) the standard deviation of X.
a
Probability And Statistics for Engineers And Scientists, Hayter, A. (2007), Chapter 3
Homework 3 (Chapter 4)
Name:__________________________________ PeopleSoft ID:_______________
Instructions:
• Homework will NOT be accepted through email or in person. Homework must be submitted through
CANVAS BEFORE the deadline.
• Write in black ink or dark pencil or type your solutions in the space provided. You must show all
work for full credit.
• Total possible points: 100
1. Determine whether or not the following table is a valid probability distribution of a discrete random
variable. Explain why or why not.
a)
x 0 1 2 3
P(x) -0.2 0.1 0.6 0.5
b)
x -1 2 3 10
P(x) 0.2 0.1 0.3 0.5
c)
x 15 16 17 18
P(x) 0.27 0.28 0.32 0.13
a
Probability And Statistics for Engineers And Scientists, Hayter, A. (2007), Chapter 3
, a
2. You and a friend play a game where you each toss a balanced coin. If the upper faces on the coins are
both tails, you win $1; if the faces are both heads, you win $5; if the coins do not match, you lost $1
(or win (-$1)). Given a single play of this game, use X to denote your winnings, find
a) the probability distribution of X.
b) the mean value of X.
c) the standard deviation of X.
a
Probability And Statistics for Engineers And Scientists, Hayter, A. (2007), Chapter 3
