Let X equal the number of knots in each 100 meters of yarn. Assume that X has a Poisson distribution with mean 2.5. Let W equal the amount of meters before the first knot is found. (a) Give the mean number of knots per meter. (b) What is the probability distribution function of W ? (c) Give the mean and variance of W. (d) Find i. P(W <= 20) ii. P(W > 40) iii. P(W > 60|W > 20)
Added by Sandra G.
Step 1
Given that X has a Poisson distribution with a mean of 2.5 knots per 100 meters, we can find the mean number of knots per meter by dividing the given mean by 100: \[ \text{Mean per meter} = \frac{2.5}{100} = 0.025 \text{ knots per meter} \] Show more…
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