Question

from a rectangulat sheet of paper ABCDwith ab =40 and ad =28 ,a semicircular portion with bc as diameter is cut off .find the area of the remaining paper

Answer 1

ad =bc =28 =d
d=28 so,r=14
$area \: of \: remainig \: page = \\ ar \: of \: rec \: - \: ar \: of \: circle$
$l \times b - \pi \: {r}^{2}$
40×28 -22×14×14/7
=504unitsq

Answer 2

Answer:

Length of paper, AB = l = 40cm

Width of paper, AD = b = 28cm

Area of paper = l × b = 40 × 28 = 1120 cm²

Diameter of semi-circle = 28cm

∴ Radius of semi-circle, r = 14cm

Thus, area of semi-circle = 1/2 πr²

= 1/2 × 22/7 × 14 × 14

= 308 cm²

∴ Area of remaining paper = 1120 – 308

= 812 cm²