Bulbs. A distributor orders 100 boxes of bulbs. A box of 10 flashbulbs contains 3 defective bulbs. A random sample of 2 bulbs is selected and tested. The probability distribution is shown in the following table, where X denotes the number of defective bulbs.

x 012 P(X = x) 0.181 0.459 0.36

a. Determine μW and σW . Round your answer for the standard deviation to three decimal places.

b. On average, how many defective bulbs are there in a box?

c. About how many defective bulbs are expected in 100 boxes?
Extending the Concepts and Skills