This is approximately equal to 0.1538
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Work Shown:
There are four cards that are labeled "9" and four cards labeled "10"
This is 4+4 = 8 cards we want out of 52 total.
So, 8/52 = (2*4)/(13*4) = 2/13
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If you wanted, you can focus on one suit, say the suit of spades. There are two cards we want here: 9 of spades, 10 of spades. There are 13 spade cards total. So this is another way to see why the answer is 2/13.
