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If the angles of a triangle are in the ratio 1 : 2 : 3, then what is the smallest angle?

A15°
B25°
C30°
D40°
Answer & Solution
Correct answer: C. 30°
1. Let the angles be x, 2x and 3x. 2. Their sum is 180°: x + 2x + 3x = 6x = 180°. 3. So x = 30°. 4. The smallest angle is x = 30°. _Source: RRB Group D CEN-02/2018 PYQ, Q.15._
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