Question

Find the perimeter and area of the figure given below. `(pi = 22/7)`

Answer 1

Length of the arc of the semicircle = `1/2 xx 2pi"r"  "units"`

= `22/7 xx 7/2  "m"` = 11 m

∴ Perimeter = Sum of all lengths of sides that form the closed boundary

P = 11 + 10 + 7 + 10 m

Perimeter = 38 m

Area = Area of the rectangle – Area of semicircle

= `("l" xx "b") - 1/2 pi"r"^2  "sq.units"`

= `(10 xx 7) - 1/2 xx 22/7 xx 7/2 xx 7/2`

= `70 - (11 xx 7)/(2 xx 2)`

= `(280 - 77)/4`

= `203/4`

= 50.75 m² (approx)

Area of the figure = 50.75 m² (approx)