Question

If P(A or B) = 0.8, P(A) = 0.1 and P(B) = 0.9, determine
P(A and B).

0.90
0.20
0.80
0.08

Answer 1

P(A or B)= P(A) + P(B) - P(A and B)
0.8=0.1+0.9-x

solve for x

Answer 2

would x be .80

Answer 3

try that again.....
.8 = .1 + .9 - x
.8 = .10 - x

Answer 4

how do you get the x alone?

Answer 5

what is keeping the x from being by itself?

Answer 6

i really dont undertand this math

Answer 7

so forget about the math....in the equation
.8 = .10 - x what is keepng the x from being by itself?

Answer 8

what is x

Answer 9

.8 = .10 - x
-.10 -.10
-.2 = -x
.2 = x