JAMB Mathematics 2011 Paper

Concept:For a regular polygon, each interior angle is found by dividing the sum of all interior angles by the number of sides $n$.Explanation:The sum of interior angles of an $n$-sided polygon is given by $(n-2) \times 180^\circ$.Here, the polygon has $n = 12$ sides.Calculate the sum: $(12 - 2) \times 180^\circ = 10 \times 180^\circ = 1800^\circ$.Now divide this total by the number of sides to get each interior angle:$$\text{Each interior angle} = \frac{1800^\circ}{12} = 150^\circ.$$Therefore, each interior angle of the regular 12-sided polygon is $150^\circ$.Answer:$150^\circ$ (Option B).