Nos of sides of a regular polygon is given by:  \(\frac{(n - 2) \times 180}{\text{n}}\) = One interior angle of the polygon.

where n = number of sides of the polygon

168 = \(\frac{(n - 2) \times 180}{\text{n}}\)

Cross multiplying, we have:

168n = 180n - 360

168n - 180n = - 360

- 12n = - 360

n = \(\frac{-360}{-12}\) = 30.