Statistics 101
Data Analysis and Statistical Inference
Extra problems on probability from the supplement
These are answers to the problems provided in the probability supplement.
1a. 20,000
b. 12,000
c. 11,000
d. 68,000
e. 10,000
2. 0.3
3. 12/216
4. for the crooked dice: 0.1875
for the fair dice: 0.1666667
5a. .18
b. .62
c. .38
d .36
e. .24
6a. 0.3311394
b. 0.3825586
c. 0.2863019
d. 0.4862
7a. .02^3
b. .98^3
8. 1 - (44/52)(43/51)(42/50)(41/49)(40/48)
9a .175
b. .23
10. No, unless the exams are independent. Clearly, this isn't the case; a person's score on midterm 1 is related her score on midterm 2.
11. .10/.30
12a. 0.06871948
b. 0.9312805
c. 0.700491
13. False.
14a. T
14b. F
14c. T
14d. F
15a) P(A4) = .10. P(A5) = .20.
b) All = 0.2.
16. No. Set A = C for a counterexample.