Question

p(a) = 0.60, p(b) = 0.20, and p(a and b) = 0.15 what is p(a or b) choices: A. 0.12, B. 0.65, C. 0.40, or D. 0.80 (Note- This is on AP3X)

Answer 1

Answer:

$p(a\ or\ b) = 0.65$

Step-by-step explanation:

Given

$p(a) = 0.60$

$p(b) = 0.20$

$p(a\ and\ b) = 0.15$

Required

$p(a\ or\ b)$

The relationship between the given parameters and the required parameters is as follows;

$p(a\ and\ b) = p(a) + p(b) - p(a\ or\ b)$

Substitute values for the known parameters

$0.15 = 0.60 + 0.20 - p(a\ or\ b)$

$0.15 = 0.80 - p(a\ or\ b)$

Collect Like Terms

$p(a\ or\ b) = 0.80 - 0.15$

$p(a\ or\ b) = 0.65$

Hence;

$p(a\ or\ b) = 0.65$