Suppose that a certain type of metalic tube contains on the average five defects per

Question

900 feet. Let X be the number of defects per 900 feet
1. What distribution does X follows ?
2. What is the probability that a tube 900 feet long contains no defects ?
3. What is the probability that a tube 1200 feet long contains more than 3
defects ?
4. Suppose in this part that X represents the number of defective of a tube that
is 900 feet long. Find P(µ − 1.2σ < X < µ + 1.2σ), and compare it with
Chebeyshev’s theorem.