Just started reading SSH... need explanation

[Asim]

well, I finally got SSHE and started reading it but somethings are confusing me. On the first section with regards to expectation.. they give a scenario where they assume you will win with AK 25% of the time. to figure out these +/-EV questions, how do you get numbers as to how often you are going to win?

secondly, the calculating outs section is extremly confusing. when they gave the example of QJ and the flop comes (10h 6c 3s)... they dont value the two overcards as full outs.. why is that, and how do you manage to figure out when something is more than half an out. I was just confused and was hoping for a simpler explanation for calculating outs.

Thanks