Question

Perimeter of a rectangular garden is $1.2\times {10}^{5}km$ and length is $0.2\times {10}^{5}km$. Find the area of the garden in standard form.

• A. $8\times {10}^{6}k{m}^2$
• B. $0.8\times {10}^{8}k{m}^2$
• C. $80\times {10}^{8}k{m}^2$
• D. $8.0\times {10}^{8}k{m}^2$

Answer 1

The correct option is D $8.0\times {10}^{8}k{m}^2$

Length of the garden $=0.2\times {10}^{5}km$

Perimeter of the graden $=1.2\times {10}^5$

$\Rightarrow 2(length+breadth)=1.2\times {10}^5$

$\Rightarrow 0.2\times {10}^5+breadth=0.6\times {10}^5$

$\Rightarrow Breadth=0.4\times {10}^{5}km$

Area of the garden $=$ length $\times$ breadth

$=0.2\times {10}^5\times 0.4\times {10}^5$

$=0.08\times {10}^{10}k{m}^2$

$8\times {10}^{8}k{m}^2$