In a certain regular polygon, the measure of each interior angle is \(10\) times the measure of each exterior angle. Find the number of sides in this regular polygon.
Let the measure of an exterior angle of the polygon be \(x\). Then \(x + 10x = 180^\circ\), so \(x = \left(\frac{180}{11}\right)^\circ\). The measure of an exterior angle of a regular polygon with \(\ell\) sides is equal to \(\left(\frac{360}{\ell}\right)^\circ\). Thus, \(\left(\frac{360}{\ell}\right)^\circ = \left(\frac{180}{11}\right)^\circ\), so the polygon has \(\boxed{22}\) sides.
Sum of interior anges = ( n-2) * 180
now divide by n to find the measure of each interior angle (n-2)* 180/n
the exterior angles are supplementary ( and exterior is 10 times bigger)
10* ( 180 - (n-2)*180/n) = (n-2)*180/n
1800 - 10(n-2)*180/n = (n-2)*180/n
1800 = 11 (n-2)*180/n
1800n = (11n-22) * 180
-180n = -3960
n = 22 sides