A card is drawn from a deck of cards numbered one through twenty. The card is NOT replaced and another card is drawn. Find the probability that a prime number is drawn and then a composite number.

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- October 11th 2008, 01:53 PMbiggestbernard1word probability problem
A card is drawn from a deck of cards numbered one through twenty. The card is NOT replaced and another card is drawn. Find the probability that a prime number is drawn and then a composite number.

- October 11th 2008, 02:19 PMfranckherve1
there are 20 cards, between the 20 first numbers,there are 8 primers numbers

so the probability that the first card is primer is 8/20=2/5

after one card is out,they are 19 cards left,and between those cards,there are there are 11 composite numbers....the probability that the second one is a composite card is 11/19

(Hi) - October 11th 2008, 02:21 PMfranckherve1
and then you multiply both...2/5.11/19=22/95