Computing odds needing to hit 2 or more cards

[top-spin]

I've finally been able to compute all the odds for all cases of outs when you only need to hit one of your outs.

I'm having a lot of trouble computing odds when you need 2 or more cards to complete your hand.

Let's say you have 67 unsuited. You need to flop two cards in order to have a good draw.

Open ended draws you need 45,58 or 89 (12 outs, must hit 2)
Inside draws you need 34,49,59,9T, or (16 outs, must hit 2)

To actually make the straight you need (24 cards must hit 3)
458,589,345,89T. How does one go about computing that?

Same with a flush, I hold something suited.

To get a 4 flush I need to hit 2 out of the 11 left to make a draw

If I flop a 3 flush, I need to hit runner runner (2 out of the 10 left)

Of course if I have a suited connector I have X chance to make a straight and Y chance of making the flush.

Here are the questions I want to be able to answer:

I have a connector, preflop, what are my odds of getting a straight by the river?
What are my odds of getting 4 to a straight on the flop?
I have 3 to a straight on the flop, what are my odds of hitting runner runner to make that straight?

I'm suited, preflop, what are my odds of getting a flush by the river?
What are my odds of getting a 4 flush on the flop?
I have 3 to a flush on the flop, what are my odds of hitting runner runner to make that flush?



Now I know I can go look these up, but I want to understand the math behind it. I've created a table for myself from what i've learned on the forums and you guys have been awesome!

http://www.vhot.com/poker/poker.pdf