WAEC Mathematics 1991 (August) Question 18

Question 18

Mensuration of Plane Shapes

In the diagram below, PXR and PYO are two semi-circles with diameters 14cm and 7cm respectively. (Take π = 22/7)
Find the area of the enclosed region, PXROY correct to the nearest whole number.

A.96cm²
B.116cm²
C.154cm²
D.192cm²
E.385cm²

Show the answer and explanation

Answer: A (96cm²)

Explanation

Large semicircle: ½ × 22/7 × 7² = 77cm². Small semicircle: ½ × 22/7 × 3.5² = 19.25cm². Total = 96.25 ≈ 96cm².