Question

How to solve a probabilitiy when it has or in the problem. Like P (A or B)?

Answer 1

Just add the probaility if they are disjoint however take out P(A and B) if the sets are not disjoint.

Answer 2

E.) was P (A and B) and then F.) is P (A or B). Earlier in the question I did P(A)=230/580 and P(B)=200/580. What should I do to find P (A or B)

Answer 3

P(A or B) =1-P'(AorB)
=1- 150/580=430/580

Answer 4

I am sorry where did you get the 150 at?

Answer 5

total P = P(A)+p(B)+P'(A or B)

Answer 6

=1

Answer 7

So if I need to solve for P (B or D) and P (B) was 200/580 and P (D) was 250/580. How do I solve this one?

Answer 8

450/580

Answer 9

Why would the problems be so different? Why did I use 1- in the first one but the second one just added the top numbers?

Answer 10

I was wrong

Answer 11

P(A+B)= P(A)+P(B)-p(aandB)

Answer 12

I know you gave me the formula but I dont understand how you got 150 still.

Answer 13

sorry for confusing you. I was wrong there.

Answer 14

haha its ok I just dont get probability at all. So can we start over real quick. I need to find P (A or B). P (A) was 230/580 and P(B) was 200/580.

Answer 15

simply add the two probabilities ?

Answer 16

but i am not sure about the intersection.