Probability of Hard Drive Failures

The video tutorial explains how to calculate the probability of avoiding data loss when using multiple hard disk drives. It starts by discussing the 12% annual failure rate of disk drives. In Part A, the tutorial demonstrates how to calculate the probability of avoiding failure with two independent drives using the rule of complements. In Part B, the same method is applied to three independent drives, showing how the probability of avoiding failure increases with more drives.

What is the annual failure rate of a disk drive as mentioned in the introduction?

• 12%

• 15%

• 20%

• 10%

In the context of the video, what does the complement of event A represent?

• At least one drive works

• Both drives work

• Both drives fail

• One drive fails

What is the probability that a single hard drive fails?

• 0.15

• 0.12

• 0.20

• 0.10

How do you calculate the probability of two independent events occurring together?

• Multiply their probabilities

• Add their probabilities

• Divide their probabilities

• Subtract their probabilities

What mathematical rule is used to find the probability of the complement of event A?

• Addition rule

• Multiplication rule

• Subtraction rule

• Division rule

What is the decimal representation of a 12% failure rate?

• 0.12

• 0.15

• 0.10

• 0.20

What is the first step in finding the probability of at least one drive working?

• Identify the complement

• Divide the probabilities

• Add the probabilities

• Calculate the sum

What is the probability that both hard drives fail in Part A?

• 0.0444

• 0.0144

• 0.0244

• 0.0344

What is the probability that at least one of the two hard drives works correctly in Part A?

• 0.9556

• 0.9656

• 0.9756

• 0.9856

What is the probability of event A in Part A?

• 0.9856

• 0.9756

• 0.9656

• 0.9556