Question

The sides of a rectangle are in the ratio 4 : 5. Find its sides if the perimeter is 90 cm.

Answer 1

\[\text{ Let the side be x cm and y cm }. \]
\[\text{ So, we have }: \]
\[ 2\left( x + y \right) = 90 \]
\[\text{ Sides are in the ratio 4: 5 }. \]
\[ \therefore y = \frac{5x}{4}\]
\[\text{ Putting the value of y }: \]
\[2\left( x + \frac{5x}{4} \right) = 90 \]
\[\frac{4x + 5x}{4} = 45\]
\[9x = 180\]
\[x = 20\]
\[ \therefore y = \frac{5 \times 20}{4} = 25\]
\[\text{ Thus, the sides of the rectangle will be 20 cm and 25 cm } . \]