stats questions

Homework 3 Due: Friday, July 13th

1. A random sample of 10 fibers is taken from a collection of 92 fibers that consists of 43 fibers of

polymer A, 17 fibers of polymer B, and 32 fibers of polymer C.

a. What is the probability that the sample does not contain any fibers of polymer B?

b. What is the probability that the sample contains exactly one fiber of polymer B?

c. What is the probability that the sample contains three fibers of polymer A, three fibers of

polymer B, and four fibers of polymer C?

2. There are 11 items of a product on a shelf in a retail outlet, and unknown to the customers, 4 of the

items are overage. Suppose that a customer takes 3 items at random.

a. What is the probability that none of the overage products are selected by the customer?

b. What is the probability that exactly 2 of the items taken by the customer are overage?

c. What is the probability that at most 2 of the items taken by the customer are overage?

3. In how many different ways, the letters in the following words could be arranged.

a. CONSTANTINOPLE

b. ABRAKADBRA

c. ASSISTANT

4. Student Engineers Council at an Indiana college has one student representative from each of the five

engineering majors (civil, electrical, industrial, materials, and mechanical). In how many ways can

a. Both a council president and a vice president be selected?

b. A president, a vice president, and a secretary be selected?

c. Two members be selected for the President’s Council?

5. consider a Little League team that has 15 players on its roster.

a. How many ways are there to select 9 players for the starting lineup?

b. How many ways are there to select 9 players for the starting lineup and a batting order for the

9 starters?

c. Suppose 5 of the 15 players are left-handed. How many ways are there to select 3 left-handed

outfielders and have all 6 other positions occupied by right-handed players?