STAT 4.1-6

An online customer service department estimates that about 15 percent of callers have to wait more than 8 minutes to have their calls answered by a person. The department conducted a simulation of 1,000 trials to estimate the probabilities that a certain number of callers out of the next 10 callers will have to wait more than 8 minutes to have their calls answered. The simulation is shown in the following histogram.

Based on the simulation, what is the probability that at most 2 of the next 10 callers will have to wait more than 8 minutes to have their calls answered?

• 0.150

• 0.190

• 0.474

• 0.526

• 0.810

Tags

CCSS.7.SP.C.8C

A high school science teacher has 78 students. Of those students, 35 are in the band and 32 are on a sports team. There are 16 students who are not in the band or on a sports team. One student from the 78 students will be selected at random. Let event B represent the event of selecting a student in the band, and let event S represent the event of selecting a student on a sports team.

Are B and S mutually exclusive events?

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Tags

CCSS.HSS.CP.A.3

The table shows data that were collected from people who attended a certain high school basketball game and indicates the team each person rooted for and whether each of these people purchased food during the game. A person who attended the game will be selected at random. Which of the following correctly interprets mutually exclusive events represented by the table?

• Rooting for the home team and rooting for the away team

• Rooting for the home team and purchasing food during the game

• Rooting for the away team and purchasing food during the game

• Rooting for the home team and not purchasing food during the game

• Not rooting for the home team and not purchasing food during the game

Tags

CCSS.HSS.CP.A.1

At a sporting event, cheerleaders will throw 50 bundled T-shirts into the crowd. The T-shirt sizes consist of 10 small, 15 medium, and the remainder either large or extra large. Suppose Ana catches a T-shirt. What is the probability that she will catch a T-shirt that is not a size small?

• 0.10

• 0.20

• 0.50

• 0.67

• 0.80

Tags

CCSS.7.SP.C.7B

A middle school chess club has 5 members: Adam, Bradley, Carol, Dave, and Ella. Two students from the club will be selected at random to participate in the county chess tournament. What is the probability that Adam and Ella will be selected?

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Tags

CCSS.HSS.CP.B.9

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• 0.02

• 0.17

• 0.32

• 0.33

• 0.50

Tags

CCSS.HSS.CP.A.3

CCSS.HSS.CP.B.8

As a promotion, the first 50 customers who entered a certain store at a mall were asked to choose from one of two discounts. The first discount choice was 20% off all purchases made that day. The second discount choice was 10% off all purchases for the week. Of those who received the discounts, 28 chose the first discount and 22 chose the second discount. One customer will be selected at random from those who received a discount. Let F represent the event that the selected person chose the first discount, and let S represent the event that the selected person chose the second discount.

Are F and S mutually exclusive events?

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Tags

CCSS.HSS.CP.A.3

A fair die with its faces numbered from 1 to 6 will be rolled. Which of the following is the best interpretation of the probability that the number landing face up will be less than 3 ?

• For many rolls of the die, the long-run relative frequency of a number less than 3 landing face up is 1/3.

• For many rolls of the die, the long-run relative frequency of a number less than 3 landing face up is 1/2.

• For many rolls of the die, the long-run relative frequency of a number less than 3 landing face up is 2/3.

• For three rolls of the die, a number less than 3 will land face up one time.

• It will take three rolls of the die before a number less than 3 lands face up for the first time.

Tags

CCSS.7.SP.C.5

Mateo plays on his school basketball team. From past history, he knows that his probability of making a basket on a free throw is 0.8. Suppose he wants to create a simulation using random numbers to estimate the probability of making at least 3 baskets on his next 5 free throw attempts. Which of the following assignments of the digits 0 to 9 could be used for the simulation?

• Let the even digits represent making a basket and the odd digits represent not making a basket.

• Let the digits 0 and 1 represent making a basket and the digits from 2 to 9 represent not making a basket.

• Let the digits from 0 to 3 represent making a basket and the digits from 4 to 9 represent not making a basket.

• Let the digits from 0 to 6 represent making a basket and the digits from 7 to 9 represent not making a basket.

• Let the digits from 0 to 7 represent making a basket and the digits 8 and 9 represent not making a basket

Tags

CCSS.7.SP.C.8C

The seniors at three high schools were surveyed about their plans after graduation. The following table shows the responses, classified by high school.

One senior from the high schools will be selected at random. What is the probability that the senior selected will not be from High School B given that the senior responded with a choice other than college?

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Tags

CCSS.HSS.CP.B.6