Question

Help Calculus

How many ways can 9 numbers be arranged on a small rotating wheel relative to a fixed point?



Consider a basket that contains 15 slips of paper numbered from 1 to 15. Two slips of paper are drawn at random. What is the probability of drawing 2 even numbers?

Answer 1

9 8 7 ... 1 = 9!
1,2,...,15
15 numbers, n odd,n-1even
n + n-1=15, n=8
first draw P(E)=7/15. P(O)=8/15
Conditional Probabilities
second draw P(E|E)=6/14, P(E|O)=7/14. P(O|E)=8/14, P(O|O)=7/14
it's been awhile since I've done these, try Baye's theorem

Answer 2

thanks!!!!