Download Competency 7 - Probability

Name: ______________________
Class: _________________
Date: _________
ID: A
Competency 7 - Probability
____
1. A single standard six-sided die is rolled. Find the probability of rolling the number 3.
2
5
1
a.
b.
1
c.
d.
3
6
6
____
2. There are 7 students participating in a spelling bee. In how many ways can the students who go
first and second in the bee be chosen?
a. 5,040 ways
c. 42 ways
b. 21 ways
d. 1 way
____
3. There are 20 beads in a bag, of which 8 beads are white, 2 beads are yellow, 6 beads are green, and the rest
are blue. Janina will choose one bead from the bag without looking. What are the odds in favor of
choosing a white bead?
a.
3 to 2
b.
1 to 1
c.
2 to 3
d.
5 to 2
____
4. Six balls numbered from 1 to 6 are placed in an urn. One ball is selected at random. Find the probability
that it is NOT number 4.
1
1
2
5
a.
b.
c.
d.
6
2
3
6
____
5. In how many ways can 11 basketball players be listed in a program?
a. 11
b. 1
c. 39,916,800
d.
55,440
____
6. A drawer contains 10 red socks, 9 white socks, and 8 blue socks. Without looking, you draw out a sock
and then draw out a second sock without returning the first sock. What is the probability that the first
sock and the second sock are both white?
1
4
5
100
a.
b.
c.
d.
9
39
39
729
____
7. A spinner is numbered from 1 through 10 with each number equally likely to occur. What is the
probability of obtaining a number less than 3 or greater than 7 in a single spin?
1
2
3
a. 2
b.
c.
d.
2
5
5
____
8. A jar contains 10 blue marbles, 4 red marbles, and 8 white marbles. What are the odds of drawing a blue
marble from the bag?
5
6
11
5
a.
b.
c.
d.
6
5
5
11
____
9. In how many different orders can you line up 7 cards on a table?
a. 5,040
b. 7
c. 1
d.
210
____ 10. A bag contains 8 yellow, 9 white, and 7 red marbles. Find the probability of picking 3 yellow marbles if
each marble is returned to the bag before the next marble is picked.
7
1
1
1
a.
b.
c.
d.
253
13824
27
12144
1
Name: ______________________
ID: A
____ 11. A spinner has five equal portions colored orange, red, blue, yellow, and green. What are the odds against
spinning a red or an orange?
3
2
2
5
a.
b.
c.
d.
2
3
5
2
____ 12. Evaluate
a.
60
C3
15
C3
6844
91
.
b.
8,555
c.
4
d.
14,190
____ 13. A coin is tossed and a die is rolled. What is the probability that the coin shows tails and the die shows 4?
1
1
2
1
a.
b.
c.
d.
6
12
3
4
____ 14. Eight balls numbered from 1 to 8 are placed in an urn. If one ball is selected at random, find the
probability that it is not number 3.
a.
3
4
b.
7
8
c.
1
2
d.
1
8
15. A number cube with faces numbered 1, 2, 3, 4, 5, and 6 is rolled. Find the probability of rolling a number
less than 7.
____ 16. A bag contains 8 red marbles, 5 white marbles, and 3 blue marbles. Find P(red or blue).
11
11
13
3
a.
b.
c.
d.
16
15
16
2
____ 17. Using a sixteen-sided number cube, what is the probability that you will roll an even number or an odd
prime number? Round to three decimals.
a.
0.813
b.
0.219
c.
0.875
d.
0.063
____ 18. In how many ways can 2 singers be selected from 5 who came to an audition?
a. 5
b. 1
c. 10
d. 20
____ 19. Suppose Ruth Ann has 4 routes she can choose from to get from school to the library, and 6 routes from
the library to her home. How many routes are there from Ruth Ann’s school to her home with a stop at
the library?
a. 24
b. 360
c. 16
d. 36
____ 20. Two cards are randomly selected from a standard 52-card deck. What is the probability of getting 2
hearts or 2 numbers less than 5 (count aces as 1)?
a. 0.149
b. 0.002
c. 0.145
d. 0.327
2
Name: ______________________
ID: A
____ 21. A jar contains 4 blue cubes, 3 blue spheres, 7 green cubes, and 2 green spheres. If you select an object at
random, what is the probability that the object is green or a cube?
a.
b.
5
4
7
16
c.
13
16
d.
4
____ 22. A bag contains 5 red marbles and 6 purple marbles. One marble is drawn at random and not replaced.
Then a second marble is drawn at random. What is the probability that the first marble is purple and the
second one is red?
3
30
5
6
a.
b.
c.
d.
11
121
6
5
____ 23. There are 10 people on the ballot for regional judges. Voters can vote for any 4. Voters can choose to
vote for 0¸ 1¸ 2¸ 3¸ or 4 judges. In how many different ways can a person vote?
a. 386
b. 252
c. 5
d. 210
____ 24. The probability that a dessert sold at a certain cafe contains chocolate is 89%. The probability that a
dessert containing chocolate also contains nuts is 29%. Find the probability that a dessert chosen at
random contains nuts given that it contains chocolate. Round to the nearest tenth of a percent.
a. 30.7%
b. 60.0%
c. 34.2%
d. 32.6%
____ 25. Two urns each contain white balls and blue balls. Urn I contains two white balls and four blue balls and
Urn II contains six white balls and six blue balls. A ball is drawn from each urn at random. What is the
probability that both balls are white?
1
5
1
1
a.
b.
c.
d.
6
36
9
3
3
ID: A
Competency 7 - Probability
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