Question

A rectangular farm has to be fenced on one long side, one short side and the diagonal. If the cost of fencing is $Rs.100$ per meter, the area of the farm is $1200m^2$ and the short side is $30m$ long, how much would the job cost?

• A. $Rs.14,000$
• B. $Rs.12,000$
• C. $Rs.7,000$
• D. $Rs.15,000$

Answer 1

The correct option is B $Rs.12,000$

Let the length of the farm be $l$ m.

Given breadth $\left(b\right)=30m$

Then, $l=\frac{Area}{Breadth}=\frac{1200m^2}{30m}=40m$

Diagonal $=\sqrt{l^2+b^2}=\sqrt{{40}^2+{30}^2}m$

$=\sqrt{1600+900}m$

$=\sqrt{2500}m=50m$

$\therefore$ Cost of fencing $=100\times$ Length of fence

$=100\times (30m+40m+50m)$

$=100\times 120m=Rs.12000$.