"Jim Cone" wrote in message
...
I would do it like this...

A1 = Total available
B1 = First amount drawn
C1 = 2nd amount drawn
D1 = IF(OR(B1A1,C1B1),"error",B1/A1*C1/A1)

Beware as the above from a one statistics class student.
'---
Jim Cone
Portland, Oregon USA .
http://www.mediafire.com/PrimitiveSoftware .
(Lottery Numbers workbook: two national lotteries & twelve state
lotteries - in the free folder)




"Jake"
wrote in message
...
If I have A2 numbers in a pot and I select B2 of them, then draw out C2,
how do I write a formula that will calculate the chance of the number of
numbers drawn in C2 matching (some or all, depending on whether B2 = C2,
but B2 is always = C2) the number of numbers in B2?

Example 100 balls, 100 to match, 100 drawn - chances are 1:1 that there
will be a match - or just displayed in an cell 1.

I know how do do the chance that A2 ball in B2 will match by using
=COMBIN(B2,A2) but thats different to what I'm asking.

Thanks, but my result seems to be giving me a better chance of matching 5
than of matching only one, hehe

10 balls total, you plan on drawing 5 balls out so you write down 5 numbers
you hope to draw, then pick 5 balls out of a hat. Chance of matching at
least 1 ball out of those 5 drawn says its 0.05, when it should be evens at
least. Chances of matching all five balls appears to be 0.25 or one in four?

If I have 10 balls total and I draw out 10 balls, the chances of me matching
at least 1, 2, 3 or all the way up to 10 should be 1 or 100%