The following cross tabulation shows household income by educational level of the head of household (Statistical Abstract of the United States: 2002).
|
|
Household Income ($1000s)
|
|
|
|
|
Under
|
25.0-
|
50.0-
|
75.0-
|
100 or
|
|
|
Education Level
|
25
|
49.9
|
74.9
|
99.9
|
more
|
Total
|
|
Not H.S. Graduate
|
9,285
|
4,093
|
1,589
|
541
|
354
|
15,862
|
|
H.S. Graduate
|
10,150
|
9,821
|
6,050
|
2,737
|
2,028
|
30,786
|
|
Some College
|
6,011
|
8,221
|
5,813
|
3,215
|
3,120
|
26,380
|
|
Bachelor's Degree
|
2,138
|
3,985
|
3,952
|
2,698
|
4,748
|
17,521
|
|
Beyond Bach. Deg.
|
813
|
1,497
|
1,815
|
1,589
|
3,765
|
9,479
|
|
Total
|
28,397
|
27,617
|
19,219
|
10,780
|
14,015
|
100,028
|
| |
|
|
|
|
|
|
|
a. Develop a joint probability table.
b. What is the probability of a head of household not being a high school graduate?
c. What is the probability of a head of household having a bachelor's degree or more education?
d. What is the probability of a household headed by someone with a bachelor's degree earning $100,000 or more?
e. What is the probability of a household having income below $25,000?
f. What is the probability of a household headed by someone with a bachelor's degree earning less than $25,000?
g. Is household income independent of educational level?