There is a spinner with 15 equal areas, numbered 1 through 15. if the spinner is spun one time, what is the probability that the result is a multiple of 5 or a multiple of 3?

7 / 15 ≈ 0.47

Explanation:

1) Probability = number of positive outcomes / number of possible outcomes

2) Positive outcomes

Multiples of 5: 5, 10, and 15
Multiples of 3: 3, 6, 9, 12, 15.
Different outcomes (cancel the repetitions): 3, 5, 6, 9, 10, 12, and 15.

Number of different positive outcomes: 7

3) Number of possible outomes: 15

4) Probability = 7 / 15 ≈ 0.47