odds on floping a set in hold'em

[Runn233]

Can someone please explain why the books say the odds of flopping a set in hold'em are about 7 to 1 even though mathematically it is about 23 to 1 (47/2=23.5)? thank you. <font color="black"> </font>

[uuDevil]

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Can someone please explain why the books say the odds of flopping a set in hold'em are about 7 to 1 even though mathematically it is about 23 to 1 (47/2=23.5)? thank you. <font color="black"> </font>

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I don't see where the 47/2 comes from. If you hold 77, odds of flopping a set:

(# Flops w/ one 7 but not FH)/(Total # flops)= 2112/19600= .107755 or 1/9.28030 or odds of ~8.3:1.

Most books show the odds of flopping a set or better. Not counting the times the you make a full house when flop comes 3 of the same rank:

((# Flops w/ one 7) + (# flops w/ 2 7's))/(Total # flops)= (2256+48)/19600= .117551 or 1/8.50694 or odds of ~7.5:1.

Another way: P(set or better)=1-P(no 7 on flop)=1-(48/50)(47/49)(46/48)= 0.117551, as above.

[Runn233]

thank you. I think I said it wrong. I went back to the book and saw that it said hitting a set after the flop not before the flop. I'm sorry i confused you.