Need help with multi-stage events (1 Viewer)

[Firnovvwen]

Okay, so those probability trees get me, especially when you put all the fractions and decimals on the "branches"..can anyone help me with that? I don't understand how to add up the probability if you have two or more branches.

Cheers.

 

[PC]

Have a read through this sheet. It might help.

 

[Firnovvwen]

Awesome, great stuff there, thanks.