Question

The radius of a circular garden is $56m$ . What would it cost to put a $4-$ round fence around this garden at a rate of $40$ rupees per metre?

Answer 1

Radius $=56$m

Circumference $=2\pi r=2\times \frac{22}{7}\times 56$

Number of fence rounds $=4$

$\Rightarrow$ Total length $=4\times 2\pi r=4\times 2\times 22\times 8$

$=64\times 22$

$=1308$metres

Cost for $1$ metre $=40$ Rs.

Cost for $1308$ metre $=1308\times 40$

$=52320$

$\therefore$ It costs Rs. $52,320$ to lay $4$ round fence around the garden.