Probability and Statistics
Review!
Name__________________________________
1.
A couple has 3 children. Draw a tree diagram and then find the following probabilities. a.
All boys 1/8 b.
All girls or all boys 2/8 c.
Exactly two boys or two girls 6/8 d.
At least one boy 7/8
B B
G
B
G
B G
B
G
G
B
G
B
G
2.
Roll two dice and multiply the numbers. a.
Write out the sample space
1,2,2,3,3,4,4,4,5,5,6,6,6,6,8,8,9,10,10,12,12,12,12,15,15,16,18,20,20,24,24,24,25
,30,30,36 b.
What is the probability the product is a multiple of 6?
13/36 c.
What is the probability that the product is less than 10?
17/36
3.
If one card is drawn from a deck, find the probability of getting these results. a.
A diamond 13/52

Probability and Statistics
Review!
Name__________________________________ b.
A 3 or a jack 8/52 c.
A 3 or a spade 16/52 d.
A red queen 2/52 e.
A red card or a seven 28/52 f.
A black card and a ten 2/52 g.
A king, a queen, or a jack 12/52 h.
A 9, or a 10 or a spade or a club 30/52
4.
At a used book sale, 100 books are adult books and 160 are children’s books. Of the adult books, 70 are nonfiction while 60 of the children’s books are non fiction. If a book is selected at random, find the probability that it is a.
Fiction
130/260 b.
Not a children’s nonfiction book
200/260 c.
An adult book or a children’s non fiction book
160/260
5.
58% of American children are read to every day by someone at home. Suppose 5 children are selected at random. What is the probability that at least 1 is read to at home?
1-P(none)  1-(.42) 4 = 0.987
6.
Of PHD students, 60% have paid assistantships. If 3students are selected at random, find the probabilities. a.
All have assistantships
(0.60) 3 = 0.216

Probability and Statistics
Review!
Name__________________________________ b.
None have assistantships
(0.40) 3 = 0.064
c.
At least 1 has a assistantship
1- P(none)  1 – (0.40) 3 = 0.936
7.
A die is rolled 7 times. Find the probability of getting at least one 3.
1-P(no three’s)  1-(5/6) 7 = 0.279
8.
A game is played by drawing 5 cards from an ordinary deck and replacing each card after it is drawn. Find the probability that at least one queen is drawn.
1-P(no queens)  1-(48/52) 5 = 0.33