B.
The random variable is
.
discrete
Week 5 Quiz

5 of 9
7/24/16 7:59 AM

12.
13.
Use technology to (a) construct and graph a probability distribution and (b) describe its shape.
The number of computers per household in a small town
Computers
0
1
2
3
Households
295
281
100
23
(a) Construct the probability distribution by completing the table below.
x
P(x)
0
0.422
1
0.402
2
0.143
3
0.033
(Round to three decimal places as needed.)
Choose the correct graph of the probability distribution.
A.
B.
C.
(b) Describe the distribution's shape. Choose the correct answer below.
Determine the required value of the missing probability to make
the distribution a discrete probability distribution.
P(4) =
!!
Number of Computers
0.1
0.2
0.3
0.4
0.5
P(x)
x
0
1
2
3
Number of Computers
0.1
0.2
0.3
0.4
0.5
P(x)
x
0
1
2
3
Number of Computers
0.1
0.2
0.3
0.4
0.5
P(x)
x
Week 5 Quiz
6 of 9
7/24/16 7:59 AM

14.
15.
The histogram shows the distribution of stops for red traffic lights a commuter must
pass through on her way to work. Use the histogram to find the mean, variance,
standard deviation, and expected value of the probability distribution.
The mean is
.
2.35
(Round to two decimal places as needed.)
The variance is
.
1.7675
(Round to four decimal places as needed.)
The standard deviation is
.
1.3295
(Round to four decimal places as needed.)
The expected value is
.
2.35
(Round to two decimal places as needed.)
Find the mean, variance, and standard deviation of the binomial distribution with the given values of n and p.
,
n = 128 p = 0.38
The mean,
, is
. (Round to the nearest tenth as needed.)
μ
48.6
The variance,
, is
. (Round to the nearest tenth as needed.)
σ
2
30.2
The standard deviation,
, is
. (Round to the nearest tenth as needed.)
σ
5.5
0
1
2
3
4
5
0.00
0.10
0.20
0.30
0.40
x
P(x)
0.05
0.23
0.35
0.14
0.15
0.08
Week 5 Quiz
7 of 9
7/24/16 7:59 AM

16.
% of women consider themselves fans of professional baseball. You randomly select six women and ask each if she
considers herself a fan of professional baseball. Complete parts (a) through (c) below.
38
(a) Construct a binomial distribution using
and
.
n = 6
p = 0.38
x
P(x)
0
0.057
1
0.209
2
0.320
3
0.262
4
0.120
5
0.029
6
0.003
(Round to the nearest thousandth as needed.)
(b) Graph the binomial distribution using a histogram and describe its shape. Choose the correct graph below.
A.
B.
C.
D.

17.