An event A has a 70% chance of occurring, an event B has a 40% of occurring and the event (A n B) has a 20% chance of occurring. The events are not unrelated.(adsbygoogle = window.adsbygoogle || []).push({});

If A does not occur what is the probability of B?

notation A' means (not A)

I have tried to use the formula P(B|A') = P(B n A')/P(A')

However Not sure if that's the right way to go and if A' would be equal to .3.

Please Help :)

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Conditional Probability

**Physics Forums | Science Articles, Homework Help, Discussion**