a deck of cards has 2 cards of blue , green , orange , red total 8 cards
what is the Probability of drawing two cards that are NOT blue
The answer is
6/8 * 5/7 = 15/28
My Q is why cant we use the negation logic to get the same answer
that is 1 - ( both blue cards )
1 - 2/8 * 1/7 = 27 /28 why is this wrong ?
Both answers are correct, but they're answers to different questions. 15/28 is the probability that *neither* card is blue. 27/28, on the other hand, is the probability that the cards are not *both* blue. The second answer is much larger than the first, because it includes all of the ways in which you might pick one blue card and one non-blue card.
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