## anonymous 5 years ago There is a 40 percent chance of rain today and a 50 percent chance of rain tomorrow. If the two events are independent, what is the probability that it will rain today or tomorrow?

1. anonymous

You need three events here: the probability it rains today and not tomorrow (.5)(.6) the probability it rains tomorrow and not today (.5)(.4) and the probability it rains both days (.5)(.4) add all those up to get a total of 0.70 or 70 percent

2. anonymous

if they are independent then the probability that they both happen is the produce. $P(A\cup B)=P(A)+P(B)-P(A\cap B)$ the first two you know, the last one you get by multiplying.

3. anonymous

Ohhhhhh I did this a while ago in class, thanks

4. anonymous

$P(A\cup B)=.4+.5-.4\times .5=.7$