- A60°
- B80°
- C40°
- D20°
Step-by-Step Solution
2k + 3k + 4k = 360°, so k = 40°: exterior angles 80°, 120°, 160°. Interior angles 100°, 60°, 20°. Smallest = 20°. (80° is the smallest exterior angle.)
Answer: D) 20°
The three exterior angles of a triangle (one at each vertex) are in the ratio 2 : 3 : 4. What is the smallest interior angle?
Class 9Exterior Angle of a TriangleGeometry — Lines and Angles
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