Finite Math Examples

P (A) = 0.9

$P (A) = 0.9$ ,

P (B) = 0.12

$P (B) = 0.12$ ,

P (A a n d B) = 0.1

$P (A a n d B) = 0.1$

Step 1

When

A

$A$ and

B

$B$ are not mutually exclusive events, the probability of

A

$A$ or

B

$B$ occurring is

P (A \cup B) = P (A) + P (B) - P (A \cap B)

$P (A \cup B) = P (A) + P (B) - P (A \cap B)$ , which is called the addition rule for not mutually exclusive events

A

$A$ and

B

$B$ .

P (A \cup B) = P (A) + P (B) - P (A \cap B)

$P (A \cup B) = P (A) + P (B) - P (A \cap B)$

Step 2

Fill in the known values.

P (A \cup B) = 0.9 + 0.12 - (0.1)

$P (A \cup B) = 0.9 + 0.12 - (0.1)$

Step 3

Multiply

- 1

$- 1$ by

0.1

$0.1$ .

P (A \cup B) = 0.9 + 0.12 - 0.1

$P (A \cup B) = 0.9 + 0.12 - 0.1$

Step 4

Add

0.9

$0.9$ and

0.12

$0.12$ .

P (A \cup B) = 1.02 - 0.1

$P (A \cup B) = 1.02 - 0.1$

Step 5

Subtract

0.1

$0.1$ from

1.02

$1.02$ .

P (A \cup B) = 0.92

$P (A \cup B) = 0.92$

Enter YOUR Problem