Probability question.

I recently played in a home tourney and got involved in an interesting first hand.

I was in BB with Q [img]/images/graemlins/diamond.gif[/img]4 [img]/images/graemlins/diamond.gif[/img], no raise preflop so 4 to the flop. Flop comes Ace [img]/images/graemlins/diamond.gif[/img] and two other diamonds. So i flop my flush and bet the pot. Player next to me raises all in. Thought about it for a minute and called. I was banking that the villain was drawing for and didnt flop his King high flush and was right. I made the call because i had a vague idea of the odds of two players flopping a flush. What is the exact odds of that happening and how am i supposed to come up with it? Kinda long-winded i know but thanks.

[jba]

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