Of the items manufactured by a certain process, 20% are defective. Of the defective items, 60% can be repaired. a. Find the probability that a randomly chosen item is defective and cannot be repaired. b. Find the probability that exactly 2 of 20 randomly chosen items are defective and cannot be repaired.

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Mathematics

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11 November, 05:42

Of the items manufactured by a certain process, 20% are defective. Of the defective items, 60% can be repaired. a. Find the probability that a randomly chosen item is defective and cannot be repaired. b. Find the probability that exactly 2 of 20 randomly chosen items are defective and cannot be repaired.

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Tatum Andersen · Answer 1

a) 0.08

b) 0.157

Step-by-step explanation:

a) P (defective) = 0.2

P (no repair) = 1 - 0.6 = 0.4

P (no repair & defective)

= 0.2*0.4 = 0.08

b) 20C2 * (0.08) ² * (0.92) ^18

= 0.156947197