Question

A box containing 10 electric bulbs, 3 of them defective and is not known which are defective. (i) In how many ways can 3 bulbs be selected? How many of these selections will include at least 2 defective bulbs? (ii) What is the probability of selecting at least 2 defective bulbs in a sample of three selected? (iii) What is the probability of selecting at most 2 non-defective bulbs in the sample of three bulbs? (iv) What is the pobability of selecting all defective bulbs in the sample?

Answer 1

1/5 is the probability