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When I meet a friend playing SimCity on Tuesday, I have a 62% chance of buying the game. When I meet another friend playing SimCity on Wednesday, I have a 84% chance of buying the game.

I need to find the total probability that I buy Simcity.

But when I add 62% to 84% that makes 146% which I am pretty sure is wrong. So how do I find the total probability in this case?

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You need to consider that if you buy SimCity on Tuesday, you won't buy it on Wednesday. – Jerry Apr 1 '13 at 17:12
The question implicitly assumes what Jerry says. – Douglas B. Staple Apr 1 '13 at 17:14
So would I have to add 62% to 38%*84% which is 0.62 + 0.3192 = 0.9392 is that correct? @Jerry – JimmyNeutronFan4Eva Apr 1 '13 at 17:16
@JimmyNeutronFan4Eva : That's it! – Jerry Apr 1 '13 at 17:20
Ok thanks. Your comment got me on the right track to understanding the problem better, so I appreciate it. @Jerry – JimmyNeutronFan4Eva Apr 1 '13 at 17:20

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