Quote:I was doing the math wrong which happens when you do math post call. Since 4% of the time, they would both do it at the same time. So the chances either of them having a 10+ TD season is 36%.

Better. The easier way to handle these cases is normally to invert the calculation. The chance of them both *failing* to do it is 0.8*0.8 = 0.64. Which gives, as you say, 36% chance of one or the other or both doing it. Your problem is that you originally counted that 4% twice.
 

Quote:For your situation:
The chances for you to win would be for both tosses to be tails. Chances for 1 toss to be tails is 50% (or .5). That means the chances for tails to occur twice is  0.5 x 0.5 or 0.25. So the chances for heads to turn up once would be 1 - 0.25 = 0.75 or 75%. For a third toss, it then becomes 1 - (0.5 x 0.5 x 0.5) = 1 - (0.125) = 0.875 or 87.5 %.

Exactly. You can't just add probabilities the way you originally did. The coin toss example makes that obvious (and the fact that it's 50-50 makes things even easier...)

---