I think they're just two extra numbers they pull out afterwards from the same pool of numbers.
Why, in the first case, is it (45-6 choose 1)? I understand the 45 is the number of options each ball could be, but what's the 6?
Hi All,
I'm trying to figure out the probability of winning the lotto. 8 numbers are drawn between 1 and 45. The first six are 'winning' numbers, the last two are the 'supplementary' numbers. To win division 1, you need to get all six winning numbers right:
\binom {45}6 = 8145060
Hence...