Probability and Sampling Review

A bag has 3 red marbles, 2 blue and 4 yellow. What is the theoretical probability of pulling a red?

• 3/10

• 3/9

• 1/9

• 1/3

The following M & M colors are in the bowl:
4 yellow, 6 orange, 3 green, 5 blue, 2 brown
What is the probability of selecting a brown candy?

• 2/18

• 1/9

• 2/20

• 1/10

What is the theoretical probability of spinning a red or a yellow?

Which statement best describes a random sample of all students in a middle school?

• Of all the students who are on the track team, the first three to finish a race are selected.

• Of all the students who are in the drama club, every third student on the roster is selected.

• Of all the students who complete an assignment, the first, third, and tenth students are selected.

• Of all the students who attend a school-wide assembly, those sitting in every third seat are selected.

In a certain population of birds, about 40 percent of the birds have a wingspan greater than 10 inches. Biologists studying the birds will create a simulation with random numbers to estimate the probability of finding 1 bird in a sample of 6 birds with a wingspan greater than 10 inches. Which of the following assignments of the digits 0 to 9 will model the population?

• Let the even digits represent birds with a wingspan greater than 10 inches and the odd digits represent birds with a wingspan less than or equal to 10 inches.

• Let the digits 0 and 1 represent birds with a wingspan greater than 10 inches and the remaining digits represent birds with a wingspan less than or equal to 10 inches.

• Let the digits from 0 to 2 represent birds with a wingspan greater than 10 inches and the remaining digits represent birds with a wingspan less than or equal to 10 inches.

• Let the digits from 0 to 3 represent birds with a wingspan greater than 10 inches and the remaining digits represent birds with a wingspan less than or equal to 10 inches.

• Let the digits from 0 to 4 represent birds with a wingspan greater than 10 inches and the remaining digits represent birds with a wingspan less than or equal to 10 inches.

Sample in which each individual or object in the entire population has an equal chance of being selected.

• Simple Event

• Sample

• Random Sample

• Scatter Plot

Which statement best describes a random sample of all students in a middle school?

• Of all the students who are on the track team, the first three to finish a race are selected.

• Of all the students who are in the drama club, every third student on the roster is selected.

• Of all the students who complete an assignment, the first, third, and tenth students are selected.

• Of all the students who attend a school-wide assembly, those sitting in every third seat are selected.

A sports bag contains 3 tennis balls, 4 baseballs, and 8 golf balls. Each is equally likely to be chosen. Which of the following models could be used to simulate this situation?

• flipping a coin fifteen times

• spinning a spinner with three equal sections

• choosing from 3 red marbles, 4 yellow marbles, and 8 blue marbles

• rolling a number cube labeled one through six fifteen times

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

• True

• False

Suzie examined 7 flowers in each planter at the mall.  Each planter has an equal number of flowers.  Is this sample of the flowers at the mall likely to be representative?

• yes

• no