Statistics Unit Review

Each person in a group of twenty people at a hotel orders one meal chosen from oatmeal, eggs, or pancakes and one hot beverage chosen from coffee or tea. One person will be selected at random from the twenty people. What is the sample space for the meal and beverage for the person selected?

• {(oatmeal, coffee), (oatmeal, tea), (eggs, coffee), (eggs, tea), (pancakes, coffee), (pancakes, tea)}

• {(oatmeal, pancakes), (oatmeal, eggs), (eggs, pancakes), (coffee, tea)}

• {(coffee, tea, oatmeal), (coffee, tea, eggs), (coffee, tea, pancakes)}

• {oatmeal, coffee, pancakes, eggs, tea}

• {(oatmeal, eggs, pancakes), (coffee, tea)}

At Mike’s favorite coffee shop, the coffee of the day is either a dark roast, a medium roast, or a light roast. From past experience, Mike knows that the probability of the coffee being a light roast is 0.15 and the probability of the coffee being a dark roast is 0.25. What is the probability of the coffee of the day not being a light roast or a dark roast on the next day that Mike visits the coffee shop?

• 0.15

• 0.25

• 0.40

• 0.60

• 0.85

Amy has 12 brown golf tees, 8 white golf tees, 10 red golf tees, 6 blue golf tees, and 12 green golf tees in her golf bag. If she selects one of the tees from the bag at random, what is the probability that she selects a tee that is not brown or blue?

A business journal reports that the probability that Internet users in the United States will use a mobile payment app is 0.60. The journal claims this indicates that out of 5 randomly selected Internet users, 3 will use the mobile payment app.

• No, because the Internet users are not independent of each other.

• No, because only 60% of all people use the Internet.

• No, because 0.60 represents probability in the long run for many Internet users.

• Yes, because Internet users are selected at random.

• Yes, because 3 out of 5 is equal to 60%.

At a local elementary school, 35 percent of all students have brown eyes, 45 percent have brown hair, and 60 percent have brown hair or brown eyes. A student will be selected at random from the school. Let E represent the event that the selected person has brown eyes, and let H represent the event that the selected person has brown hair.

Are E and H mutually exclusive events?

• Yes, because P(E∩H)=0.

• Yes, because P(E∩H)=0.2.

• Yes, because P(E∩H)=0.6.

• No, because P(E∩H)=0.2.

• No, because P(E∩H)=0.6.

For the lunch special at a high school cafeteria, students can get either salad or french fries as a side order. The following table shows the number of each side order for the lunch specials purchased on one day, classified by the grade of the student.

From those who purchased the lunch special that day, one student will be selected at random. What is the probability that the student selected will be in grade 10 given that the student ordered french fries as the side order?

A high school theater club has 40 students, of whom 6 are left-handed. Two students from the club will be selected at random, one at a time without replacement. What is the probability that the 2 students selected will both be left-handed?

At a large high school 40 percent of the students walk to school, 32 percent of the students have been late to school at least once, and 37.5 percent of the students who walk to school have been late to school at least once. One student from the school will be selected at random. What is the probability that the student selected will be one who both walks to school and has been late to school at least once?

• 0.12

• 0.15

• 0.1875

• 0.345

• 0.72

Given independent events A and B such that P(A)=0.3 and P(B)=0.5, which of the following is a correct statement?

• P(A|B)=0

• P(B|A)=0.3

• P(A|B)=0.5

• P(A∪B)=0.65

• P(A∪B)=0.80

While investigating customer complaints, the customer relations department of Sonic Air found that 15 percent of the flights arrive early and 25 percent arrive on time. Additionally, 65 percent of the flights are overbooked, and 72 percent are late or not overbooked. One Sonic Air flight will be selected at random. What is the probability that the flight selected will be late and not overbooked?

• 0.21

• 0.23

• 0.26

• 0.39

• 0.72