If all measurements are in centimetres, the area of the figure below is:

Explanation

This is a rectangle shape and three halves of circles.  Two halves are taken away from the rectangle area and one half is added to the rectangle area.  These half-circles are all the same in area.

In other words

Area = rectangle area - half circle + half circle - half circle   

Two half circles cancel each other    

Area = rectangle area - half circle   

Rectangle area = 6 * 15 = 90 cm²

half circle = (π * 2.5² ) / 2 = 9.8125 cm²

Area = 90 - 9.8125 = 80.18 cm²