Katie B. answered 04/11/17
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So, there are 4 face cards for every suit (dismonds, hearts, etc.) i.e. 4 out of every 13 cards. Since there are 4 suits, the probability of picking a face card (the first time) is 16 / 52 (simplified to 4 / 13).
This means the probability of NOT picking a face card the first time is 9 / 13. Keep that number in mind.
Now we're left with 1 fewer non-face card, but the face cards are intact. The total has decreased from 52 to 51.
So, we go from a probability of 9 / 13 to (51 - 16) / 51 of picking a non-face card = 35 / 51 (2nd time).
Now our total reduces to 50 cards. Keep in mind there are still 16 face cards. So, the non-face cards = 50 - 16 = 34.
Probability of picking another non-face card = 34 / 50 (simplified to 17 / 25).
The probability, therefore, of picking 3 non-face cards = 9 x 35 x 17
13 x 51 x 25
Easy to solve now?