Q33 of 128 Page 13

A box contains 90 discs, numbered from 1 to 90. If one disc is drawn at random from the box, the probability that it bears a prime number less than 23, is

Total numbers of elementary events are: 90

Let E be the event of drawing prime number less than 23


Favorable outcomes are: 2, 3, 5, 7, 11, 13, 17, 19


Numbers of favorable outcomes are: 8


P (prime number less than 23) = P (E) = 8/90 = 4/45

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