Question

Correct the perimeter of the figure given to one decimal place

• A. $56.0m$
• B. $56.6m$
• C. $57.2m$
• D. $57.9m$

Answer 1

The correct option is B $56.6m$

The corners are quadrants, i.e.,
$\frac{1}{4}\times 2\times \pi \times 2=\pi$
For 4 corners, we have peri-meterof quadrants $4\pi$
Perimeter of horizontal portions $=2(20-4)=32$ m
Perimeter of vertical portions $=2(10-4)=12$ m
Hence total perimeter $=44+4\pi$
$=44+\frac{88}{7}=\frac{308+88}{7}$
$=56.57\approx 56.6m$