Question

Saima wants to put a lace on the edge of a circular table cover of diameter $1.5$ m. Find the length of the lace required and also find its cost if one meter of the lace costs Rs. 20?

Answer 1

Given diameter of circle $1.5m$

Then, radius of circle is $r$ $=\frac{D}{2}=\frac{1.5}{2}m$

Now total length of lace $=$ circumference of circle$=2\pi r$

$=2\times 3.14\times \frac{1.5}{2}$

$=3.14\times 1.5$

$=4.71m$

Now, given 1 m cost of lace $=20rs$

Then cost of total lace

$=4.71\times 20$

$=94.2$ Rs