Question

From a rectangular sheet of paper ABCD with AB = 40 cm and AD = 28 cm, a semi-circular portion with BC as diameteris cut off. Find the area of remining paper (use π = 22/7)

Answer 1

area of rectangle -area of semicircle

area of rectangle=40×28=1120cm²

area of semicircle =πr²/2

=22(14)(14)/2(7)

=308 cm²

area of remaining part

=1200-308

=892cm²

Answer 2

Answer:812 square cm

Step-by-step explanation:since ABCD is a rectangle,

AB=DC=40cm

AD=BC=28cm

Area of rectangle ABCD

=length ×breadth

=40×28

=1120 square cm

In a semicircle ,

Diameter =BC=28cm

Therefore radius =14cm

Area of a semicircle

=1/2 × 22/7 × r^2

=1/2 × 22/7×14×14

=22×14

=308 square cm

Area of remaining paper

=area of rectangle -area of the semicircle

=1120 - 308

=812 square cm .

Therefore, area of the remaining paper is 812 square cm.