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Find the Magnitude, in Radians and Degrees, of the Interior Angle of a Regular Duodecagon.

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Question

Find the magnitude, in radians and degrees, of the interior angle of a regular duodecagon.

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Solution

\[\text{ Sum of the interior angles of the polygon }= \left( n - 2 \right)\pi\]
Number of sides in the duodecagon = 12 
\[ \therefore \text{ Sum of the interior angles of the duodecagon }= \left( 12 - 2 \right)\pi = 10\pi\]
\[\text{ Each angle of the duodecagon }= \frac{\text{ Sum of the interior angles of the polygon }}{\text{ Number of sides }} = \frac{10\pi}{12} = \frac{5\pi}{6}\text{ rad }\]
\[\text{ Each angle of duodecagon }= \left( \frac{5\pi}{6} \times \frac{180}{\pi} \right)^\circ= {150}^\circ\]

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Chapter 4: Measurement of Angles - Exercise 4.1 [Page 15]

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R.D. Sharma Mathematics [English] Class 11
Chapter 4 Measurement of Angles
Exercise 4.1 | Q 5.4 | Page 15

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