The figure shows a rectangular field JKLM. Cody walked from J to K to L to M and he covered a distance of 58 cm. Julie walked from K to L to M to J and she covered a distance of 38 cm.
- What is the perimeter of the field?
- Some construction work was undertaken to the same field and a semi-circular part was removed from it. What Is the perimeter of the field after the construction? (Take π = 227)
(a)
Lets assume Length → L and Breadth → B
Cody total covered distance
L + L + B = 58
2 L + B = 58 = A1
Julie total covered distance
B + L + B = 38
2 B + L = 38 = A2
A1 + A2
3 B + 3 L = 96
B + L = 96 ÷ 3 = 32 cm
Perimeter of the field
= 2 (B + L)
= 2 x 32
= 64 cm
(b)
Circumference of the semicircle
=
227 x 7 x
12 = 11 cm
Perimeter of the remaining field
= 64 + 11 - 7
= 68 cm
Answer(s): (a) 64 cm; (b) 68 cm