Problem 10 · Count in separate cases · 3 points
Made by AI and not reviewed by a real person.
Maya picks three spots in the row. How many different groups of spots can she pick that include both kinds of shapes?
- 10
- 6
- 3
- 8
- 9
Show a hint
- Think about the circles as you make groups, and be careful not to count the same group twice.
- What happens if Maya picks one circle? What happens if she picks both?
Show the answer and solution
Answer: E — 9
With one circle, Maya can choose either circle and two of the three triangles, making 6 groups. With both circles, she can choose any one of the three triangles, making 3 more groups. That gives 9 groups. The answer 6 misses the groups that use both circles.