AP Stats Probability Review

What is the law of large numbers?

• simulated probabilities seem to get farther from the true probability as the number of trials increase

• simulated probabilities seem to get closer to the true probability as the number of trials increases

• simulated probabilities seem to get closer to the true probability as the number of trials decreases

• simulated probabilities seem to get farther from the true probability as the number of trials decreases

Mutually exclusive events...

• Always occur at the same time

• Sometimes occur at the same time

• Never occur at the same time

• don't exist

Parked Car plays on the soccer team. From past games he knows his probability of making a goal is 0.8 Suppose he wants to create a simulation using random numbers to estimate the probability of making at least 3 of his 5 next goals. Which of the following assignments of the digits 0 to 9 could be used for the simulation.

• Let the even digits represent making a goal and the odd digits represent not making a goal

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

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

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

A local pet store has 100 rats. There are 20 brown rats, 30 white rats, and the remainder of the rats are black. Suppose Danyelle picks a random rat. What is the probability that the rat she picks is not brown?

• 0.2

• I'm not on the probability horse

• 0.5

• 0.8

A spinner is divided into 8 sectors of equal size, and the spinner is equally likely to land in any sector. 6 of the 8 sectors are blue, and the remaining sectors are red. Which of the following is the best interpretation of the probability that one spin of the spinner will land in a blue sector

• For every 8 spins, the spinner will land in the blue sector 6 times

• For many spins, the long-run relative frequency with which the spinner will land in a blue sector is 3/4

• For many spins, the long-run relative frequency with which the spinner will land in a shaded blue is 1/4

• For every 8 spins, the spinner will land in the blue sector 2 times

At a local grocery store, 50% of all employees have brown eyes, 40% have brown hair, and 65% of employees have brown hair or brown eyes. An employee will be selected at random from the store. Let A represent the event that the selected person has brown eyes, and let B represent the event that the selected person has brown hair. Are B and K mutually exclusive events?

• Yes, because P(A∩B)= 0

• Yes, because P(A∩B)=0.9

• No, because P(A∩B)=0.25

• No, because P(A∩B)=0.9

• Yes, because P(A∩B)= 0.25

A softball team has 30 players, of whom 5 bat left handed. 2 players on the team will be selected at random, one at a time without replacement. What is the probability that the 2 selected players bat left handed?

• 25/900

• 20/900

• 20/870

• 25/870

One student from Montgomery will be selected at random. Let A be the event that the selected student watches Veggie Tales, and let B be the event that the selected student drives to school. If P(A∩B)=0.1 and P(B|A)=0.8, what is the probability that the selected student watches Veggie Tales?

• 0.1

• 0.125

• 0.8

• 0.9

Given independent events A and B such that P(A)=0.15 and P(B)=0.8, which of the following is a correct statement?

• P(A|B)= 0.8

• P(B|A)=0.15

• P(AUB)=0.95

• P(AUB)=0.83

Consider two events, A and B, where P(A)=0.4, P(B)=0.6, and P(A and B)=0.25. Are the events of A and B independent?

• Yes

• No