Suppose that, on average, 4 percent of all CD drives received by a computer company are defective. The company has adopted the following policy: Sample 50 CD drives in each shipment, and accept the shipment if none are defective. Using this information, determine the following:
What fraction of shipments will be accepted?
If the policy changes so that a shipment is accepted if only one CD drive in the sample is defective, what fraction of shipments will be accepted?
What is the probability that a sample size of 50 will contain at least 10 defective CD drives?
Using the airline overbooking data:
Determine how the probability of overbooking varies as the number of tickets sold varies from 100 through 115. Hint: Use a one-way data table.
Show how the probability of overbooking varies as the number of tickets sold varies from 100 through 115, and the probability that a ticket holder shows up varies from 80 percent through 95 percent. Hint: Use a two-way data table.
Suppose that during each year, a given mutual fund has a 50 percent chance of beating the Standard & Poor’s 500 Stock Index (S&P Index). In a group of 100 mutual funds, what is the probability that at least 10 funds will beat the S&P Index during at least 8 out of 10 years?
Professional basketball player Steve Nash is a 90-percent foul shooter.
If he shoots 100 free throws, what is the probability that he will miss more than 15 shots?
How good a foul shooter would Steve Nash be if he had only a 5 percent chance of making fewer than 90 free throws out of 100 attempts? Hint: Use Goal Seek.
When tested for extra sensory perception (ESP), participants are asked to identify the shape of a card from a 25-card deck. The deck consists of 5 cards of each of five shapes. If a person identifies 12 cards correctly, what would you conclude?
Suppose that in a group of 100 people, 20 have the flu and 80 do not. If we randomly select 30 people, what is the chance that at least 10 people have the flu?
A student is selling magazines for a school fundraiser. There is a 20 percent chance that a given house will buy a magazine. He needs to sell five magazines. Determine the probability that he will need to visit 5, 6, 7,…, 100 houses to sell five magazines.