Question

P (a) =0.60, p(b) = 0.25, and p(a and b) =0.15 what is p(a or b) ?

Answer 1

Answer:

C is the correct option

Step-by-step explanation:

To find the probability of P(a or b) we will use  the formula:

P(a or b)= P(a)+ P(b) - P(a-b)

Now put the given values in the formula:

P(a or b)= 0.60+0.25-0.15

P(a or b)=0.85 - 0.15

P(a or b)= 0.70

Thus the correct option is C....

Answer 2

Answer: Option C

$P (A\ or\ B) = 0.70$

Step-by-step explanation:

If A and B are events that are not mutually exciting, then it is true that:

$P (A\ or\ B) = P (A) + P (B) - P (A\ and\ B)$

In this case we know $P(A)$, $P(B)$ and we also know $P (A\ and\ B)$

$P(A)=0.60$

$P(B) = 0.25$

$P(A\ and\ B)=0.15$

Therefore we have that:

$P (A\ or\ B) = 0.60 + 0.25 - 0.15$

$P (A\ or\ B) = 0.60 + 0.1$

$P (A\ or\ B) = 0.70$