What are the odds of a board being 5 cards of one suit?

[Black winter day]

And how do you calculate it?
Is it 12/51*11/50*10/49*9/48?

[donkeyradish]

4 Royal Flushes
36 Straight Flushes
5,108 Flushes

Divide 5148 by 2,598,960 the number of ways to deal 5 cards

(The formula you suggest looks right too)

[fiskebent]

Yes, Black. That's the way to calculate it.