A parallelogram shaped notice board and a triangular shaped sign board have the same base and same area. If the sides of the triangle are 18 \(cm\), 20 \(cm\) and 22 \(cm\), and the parallelogram stands on the base 20 \(cm\), find the height of the parallelogram shaped notice board. (Use \(\sqrt{2} = 1.41\))
Height of the parallelogram shaped notice board