# Emily is playing a board game that has a spinner divided into equal sections numbered 1 to 18. The probability of the spinner landing on an even number or a multiple of 3 ?

##### 1 Answer

#### Explanation:

We want to find the probability of landing on an even number **or** a multiple of 3, so we should use the addition rule for the union of two events:

Let's make

- A = the probability of landing on an even number, and
- B = the probability of landing on a multiple of 3

What is **P(A)** (the probability of landing on an even number? 2, 4, 6, 8, 10, 12, 14, 16, and 18 are all even, so P(A) is

What is **P(B)** (the probability of landing on a multiple of 3? 3, 6, 9, 12, 15, and 18 are multiples of 3, so P(B) is

What is **P(A and B)** (the probability of landing on an even number that's also a multiple of 3)? 6, 12, and 18 are all even AND multiples of 3. So P(A and B) is

Now we can plug our values into the equation!