You can put this solution on YOUR website! # of ways to pick 11 diamonds: 13C11 = 13*12/1*2 = 78
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# of ways to pick 2 other cards: 39C2 = 39*38/1*2 = 19*39 = 741
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# of ways to have a 13-card hand with exactly 11 diamonds: 78*741 = 57,798
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Cheers,
Stan H.