Hi guys, It's been 20 years since I left college so I have forgotten how to calculate probability. It is probably very easy so can somebody just explain how I can get the odds/probability of winning. If I create prize A with odds = 10/1 (one in ten chance of winning) Prize B has odds of winning = 75/1 (one in 75 chance of winning Prize C has odds of winning = 90/1 ( one in 90 chance of winning) If these odds are layered on top of each other what are my chances of winning a prize. can you also explain how its done rather than just posting the odds answer. I presume my answer would be less than 10/1 as if there were only one prize (with A being the prize) but I now also have a chance of winning prize B or C also so that would mean it would be fractionally better than one in ten? Any help greatly appreciated.