Question

P(A or B) = .4 and P (A and B) +.1, Find P(A) + P(B)

Answer 1

P(A or B) = P(A) + P(B) - P(A and B)
therefore 4 = P(A) + P(B) - 1
P(A) + P(B)=3

Answer 2

P(A) + P(B)=4+1=5

Answer 3

o...sry you are right...

Answer 4

They both look right!? Idk!!

Answer 5

If they are mutually exclusive then Salmon answer is right, if they are not then you are right. But it does not say on my homework assignment.

Answer 6

@salmon @eliassaab do you notice the little dot in ".4" and ".1"

Answer 7

not sure P(A) + P(B) = 3 or more
we knowed that maximum value of P(A) = 1, also for P(B)

Answer 8

So close!
I think I am just going to use one of their answers. I am not sure, thanks for all help!

Answer 9

P(A or B) = P(A) + P(B) - P(A and B)
therefore 0.4 = P(A) + P(B) - 0.1
P(A) + P(B)=0.4+0.1=0.5
This should be the most appropriate answer satisfying all the above comments

Answer 10

Thank you!!