Calculations from "The Theory of Poker"

[TPS_Reports]

I have just started reading "The Theory of Poker" and am trying to verify some of the listed probabilities. In particular, p.38 contains a discussion on 7-card stud where your first three cards are spades. There are seven other cards showing (8 player game). The table then lists the probabilities for making the flush if, of the 7 other cards showing, 0,1,2,3,or 4 of them are spades. The probabilities listed are as follows:

# Showing.................Chance for Flush %
0......................... 23.6
1......................... 19.6
2.......................... 15.8
3...........................12.3
4...........................9.1

I think I am able to calculate this if you only received two more cards (10/42)*(9/41) = 5.2%, but I don't know how to do this for 7 card. I would greatly appreciate any help you could give me. Does anyone know of a good source that lists some of the common probability formulas? Thanks again.

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