Cloth is sold by the bolt where a bolt is 15 yards of material. If the expected number of blemishes per yard is 0.1 find the probability that:

(a) A yard of cloth contains 1 or more blemishes.
(b) A bolt contains at most 2 blemishes.
(c) A lot of 30 bolts contains at least 50 blemishes.

(a) The probability that a yard of cloth contains 1 or more blemishes is 0.0952.

(b) The probability that a yard of cloth contains at most 1 blemishes is 0.9953.

(c) The probability that in a lot of 30 bolts contains at least 50 blemishes is 0.2468.

Step-by-step explanation:

Let X = number of blemishes per yard of material.

The expected value of X is:

E (X) = λ = 0.1

The random variable  X follows a Poisson distribution with parameter λ = 0.10

The probability function of a Poisson distribution is:

(a)

Compute the probability that a yard of cloth contains 1 or more blemishes as follows:

P (X ≥ 1) = 1 - P (X < 1)

             = 1 - P (X = 0)

Thus, the probability that a yard of cloth contains 1 or more blemishes is 0.0952.

(b)

Compute the probability that a yard of cloth contains at most 1 blemishes as follows:

P (X ≤ 1) = P (X = 0) + P (X = 1)

Thus, the probability that a yard of cloth contains at most 1 blemishes is 0.9953.

(c)

In a lot of 30 bolts the expected number of yards of material is:

Compute the probability that in a lot of 30 bolts contains at least 50 blemishes as follows:

P (X ≥ 50) = 1 - P (X < 50)

**Use an online calculator or Excel to compute the probability.

Thus, the probability that in a lot of 30 bolts contains at least 50 blemishes is 0.2468.

9 sandwiches per hour

step-by-step explanation:

when we have a rate, we want a 1 in the denominator

27/3 = 9

27 sandwiches/ 3 hours = 9 sandwiches/hour