Use the following to answer the next three questions. David\'s gasoline station
ID: 3156377 • Letter: U
Question
Use the following to answer the next three questions.
David's gasoline station offers 4 cents off per gallon if the customer pays in cash and does not use a credit card. Past evidence indicates that 35% of all customers pay in cash. During a one-hour period 25 customers buy gasoline at this station.
1. What is the probability that exactly 10 pay in cash?
2. What is the probability that between four and eight, inclusive, customers pay in cash?
3. What is the probability that more than ten and less than fifteen customers pay in cash?
Explanation / Answer
David's gasoline station offers 4 cents off per gallon if the customer pays in cash and does not use a credit card. Past evidence indicates that 35% of all customers pay in cash. During a one-hour period 25 customers buy gasoline at this station.
P( x=10) =0.1409
P( 4x8) = P( x=4)+P( x=5)+ P( x=6)+P( x=7)+P( x=8)
=0.0224+0.0506+0.0908+0.1327+0.1607
=0.4571
3. What is the probability that more than ten and less than fifteen customers pay in cash?
P( 10 <x<15) = P( x=11)+P( x=12)+ P( x=13)+P( x=14)
=0.1034+0.0650+0.0350+0.0161
=0.2195
p=0.35, n=25
P(X=x) = (nCx) px (1-p)n-x
Binomial Probabilities Table
X
P(X)
0
0.0000
1
0.0003
2
0.0018
3
0.0076
4
0.0224
5
0.0506
6
0.0908
7
0.1327
8
0.1607
9
0.1635
10
0.1409
11
0.1034
12
0.0650
13
0.0350
14
0.0161
15
0.0064
Binomial Probabilities Table
X
P(X)
0
0.0000
1
0.0003
2
0.0018
3
0.0076
4
0.0224
5
0.0506
6
0.0908
7
0.1327
8
0.1607
9
0.1635
10
0.1409
11
0.1034
12
0.0650
13
0.0350
14
0.0161
15
0.0064
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.