試題詳解

213. A factory tests 100 light bulbs for defects. The probability that a bulb is defective is 0.02. The occurrences of defects among the light bulbs are mutually independent events. Calculate the probability that exactly two are defective given that the number of defective bulbs is two or fewer.
(A) 0.133
(B) 0.271
(C) 0.273
(D) 0.404
(E) 0.677