A computer manufacturer claims that chips it makes are so accurate that there is only 1/2000 probability of getting a defective chip. A salesman at a local store purchased 5 chips and claimed that 2 of them were defective.
a). Find the probability of getting exactly 2 defective chips when buying 5 chips.
b). Find the probability of getting at least 2 defective chips when buying 5 chips.
c). Does the salesman's claim of getting 2 defective chips seem valid? Explain.