Question

If the perimeter of a rectangle is 23 cm and its width is 4 cm, then find the length of the rectangle.

• A. 7.5 cm
• B. 8.5 cm
• C. 3.8 cm
• D. 4.6 cm

Answer 1

The correct option is A

7.5 cm

Let the length of the rectangle be $x$ cm.
The perimeter is calculated as,
$2\times (\text{length}+\text{width})$.

$\therefore 2\times (\text{length}+\text{width})=23\text{cm}\Rightarrow 2\times (x+4)=23\Rightarrow 2x+8=23\Rightarrow 2x=23-8\Rightarrow 2x=15\Rightarrow x=\frac{15}{2}$

$\therefore$ The length of the rectangle is $\frac{15}{2}$ cm.