Probability

Multiple Choice

_______ is the entire group of objects or individuals considered for a survey.

• Sample

• Population

• Random Sample

• Quartile

Multiple Choice

_______ is a part of a group being surveyed.

• Sample

• Population

• Random Sample

• Quartile

Multiple Choice

True or False: all samples lead to a good prediction about an entire population.

• True

• False

Multiple Choice

MB wants to know the average student’s opinion of the tardy policy at her school. Which group of students should she survey in order to achieve the most accurate results?

• thirty students who are often tardy

• thirty students who are rarely tardy

• thirty of her friends

• thirty randomly selected students from her school

Multiple Choice

A school surveys all 7th grade boys to determine what to sell in the school store.  This sample is _________.

• Biased

• Unbiased

• Representative

• true

Multiple Choice

The choir director in a high school wants to know how the students in the school feel about singing. If the director selects 100 girls and 100 boys to complete a survey, which method will result in a biased sample?

• The students will be selected from the choir

• The students will be selected randomly throughout the school

• The students will be selected randomly on Wednesday afternoon.

• The choir director will randomly select five students from each of the forty homerooms in the school

Theoretical Probability

Experimental Probability

Multiple Choice

Experimental Probability is:

• What Will happen 

• What actually happens

• What should happen

• What I think Happens

Multiple Choice

Theoretical Probability is:

• What will happen

• What should happen

• What I want to happen

• What does happen

Remember:

Probability is the chance something will happen on a scale from 0 to 1.

Multiple Choice

What is the theoretical probability of the spinner landing on yellow?

• $$\frac{1}{3}$$

• $$\frac{1}{4}$$

• $$\frac{1}{2}$$

• $$\frac{2}{3}$$

Multiple Choice

The table shows the results of 50 rolls of a number cube. According to the data in the table, what was the experimental probability of rolling a 1? (Simplify if needed)

Multiple Choice

What is the theoretical probability of randomly picking a Purple marble from Molly's Sack of Marbles?

• $$\frac{4}{5}$$

• $$\frac{3}{15}$$

• $$\frac{2}{15}$$

• $$\frac{8}{21}$$

How many prefer Social Studies?

How many prefer Science?

How many prefer Language Arts?

Multiple Choice

• 2

• 4

• 8

• 16

Multiple Choice

Jill rolls a number cube 30 times.

How many times should she expect it to land on a 4?

• 5 times

• 4 times

• 6 times

• 8 times

Multiple Choice

The spinner is spun 25 times.

What is the best prediction for the number of times it will land on red?

• 5 times

• 3 times

• 6 times

• 20 times

Independent & Dependent Events

• Independent - One activity does not effect the outcome of a different activity. (Drawing marbles from a bag, but putting them back each time.)

• Dependent - One activity DOES effect the outcome of another activity. (Drawing a card from a deck of cards, not putting it back and drawing another.)

1.

2.

The set of all possible outcomes of one or more events is called the
sample space.

A compound event consists of two or more events.
The probability of a compound event is the ratio of the number of
favorable outcomes to the number of possible outcomes.

Multiple Choice

What is the probability of rolling a dice and landing on a 4, and then rolling the dice again and landing on any even number?

• 1 ⁄ 6

• 1 ⁄ 8

• 1 ⁄ 2

• 1 ⁄ 12

Multiple Choice

A coin is tossed and then the spinner is spun. Determine the probability that you toss Heads and spin a Red.

• 1/6

• 1/10

• 0

• 1/12

Probability of a Dependent Event

The probability of two dependent events A and B is the probability of A times the probability of B after A occurs.

P(A and B) = P(A)⋅P(B after A)

People are randomly chosen to be game show contestants from an audience of 100 people. You are with 5 of your relatives and 6 other friends. What is the probability that one of your relatives is chosen fi rst, and then one of your friends is chosen second?

2. Alyssa has a bag of marbles. There
are 6 red, 8 blue, 5 green, 9 yellow, and
2 white marbles, all the same size and
shape.
a.

What is the probability of randomly
choosing a white marble?

b.

What is the probability of randomly
choosing a white marble, then a
green marble (without
replacement)?

1.

There are 4 purple, 3 red, 2 green, 2,
yellow, and 4 blue balloons.

Multiple Choice

Determine if the following events are dependent or independent.
Anna flips a coin two times.

• Independent

• Dependent

Multiple Select

You randomly draw a marble from a bag of marbles. You get a red and don't put it back into the bag. You draw another marble out of the bag and get a yellow.

• Independent

• Dependent

Multiple Choice

A box contains 5 purple marbles, 3 green marbles and 2 orange marbles. Draws are made without replacement.P(both marbles are purple)

• 2/9

• 1/3

• 1/2

• 1/4

Multiple Choice

A bag contains some red-colored and some blue-colored marbles. First a red-colored marble is drawn and then, without replacing the first marble, a blue-colored marble is drawn. Are the two events dependent or independent?

• Independent

• Dependent

Multiple Choice

The outcome of one event does influence the outcome of the other event

• mutually exclusive event

• probability

• dependent event

• simple probability

Multiple Choice

The outcome of one event does not influence the outcome of the other event

• independent event

• tree diagram

• simple event

• odds