The figure shows 2 quarter circles and a rectangle. The radius of the big quarter circle is 18 m. The radius of the small quarter circle is 9 m. Find the difference in the areas between the two shaded parts S and T. (Take π = 3.14 and give your answer correct to 1 decimal place.)
Area of the big quadrant
= ¹₄ x 3.14 x 18 x 18
= 254.34 m²

Area of the small quadrant
= ¹₄ x 3.14 x 9 x 9
= 63.585 m²

Area of the rectangle
= 18 x 9
= 162 m²

Difference in the areas between the two shaded parts S and T
= Area of the big quadrant - (Area of the small quadrant + Area of the rectangle)
= 254.34 - (63.585 + 162)
= 254.34 - 225.585
= 28.755 
≈ 28.8 m² (Correct to 1 decimal place)

Answer(s): 28.8 m²