A box contains 8 yellow beads, 9 black beads, and 3 purple beads. If one bead is chosen without looking, what is the probability that it is black?
- 8 yellow beads
- 9 black beads
- 3 purple beads
Choose the best answer.
Note
For basic probability, compare the number of favorable outcomes with the total number of equally likely outcomes.
- Count the favorable outcomes first: there are 9 black beads.
- Then count all possible outcomes: 8 + 9 + 3 = 20.
- Probability means favorable outcomes divided by total outcomes, so the probability is 9/20, which simplifies to 9/20.
The correct answer is 9/20. This matches the calculation or definition, so students should focus on the reasoning rather than only memorizing the final value.