Length of tape required to cover the edges of a semicircular disc of r

1.	Length of tape required to cover the edges of a semicircular disc of radius 10 cm is (a) 62.8 cm (b) 51.4 cm (c) 31.4 cm (d) 15.7 cm
Answer» (b) 51.4 cm From the question it is given that, radius of semicircular disc 10 cm We know that, perimeter of semicircular disc = circumference of semicircle + diameter Circumference of semicircle = 2πr/2 = πr = (22/7) × 10 = 31.4 cm Then, total tape required = 31.4 + 10 + 10 = 51.4 cm

Length of tape required to cover the edges of a semicircular disc of radius 10 cm is (a) 62.8 cm (b) 51.4 cm (c) 31.4 cm (d) 15.7 cm

Answer»

(b) 51.4 cm

From the question it is given that, radius of semicircular disc 10 cm

We know that, perimeter of semicircular disc = circumference of semicircle + diameter

Circumference of semicircle = 2πr/2

= πr

= (22/7) × 10

= 31.4 cm

Then, total tape required = 31.4 + 10 + 10

= 51.4 cm