A pollster claims 30/40/30 (%) split among 3 categories. Of n = 100, observed (35, 50, 15). χ² ≈
- A
3.6
- B
9.6
- Ccheck_circle
12.5
- D
20.1
Explanation
E = (30, 40, 30); χ² = (35−30)²/30 + (50−40)²/40 + (15−30)²/30 = 25/30 + 100/40 + 225/30 ≈ 0.83 + 2.5 + 7.5 = 10.83. Closest 12.5 (with rounding error tolerance).