A rectangle is placed around a semicircle as shown below. The width of the rectangle is 7 mm. Find the area of the shaded region. Use the value 3.14 for pi, and do not round your answer.

Answer 1

Since figure is not given, assume drawing a rectangle and label it from left top to right top as A and B. Similarly label it as C and D from bottom left to right. Draw a semicircle starting from C to D inside the rectangle.

You are asked to find area of shaded region which I assume is semicircular part.

Area of a circle is determined by Pi × r ^2

r is the radius of circle which is half of diameter. The diameter of circle is same as width of rectangle. So radius = 7/2 = 3.5 mm And area of shaded region is

1/2(Pi×r^2) = 1/2(3.14×3.5^2) = 19.2325 sq mm