alleryStart learning →Interior angles are in the ratio 1:2:3. What is the exterior angle at the smallest angle?
A150°
B30°
C120°
D90°
Answer & Solution
Correct answer: A. 150°
The angles are 30°, 60° and 90°, so the exterior angle at the 30° vertex is 180° minus 30°, which is 150°.
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