The perimeter and length of a rectangle are in the ratio of 8 : 1, and the area of the rectangle is 1323 cm2. Find the length of the rectangle.
Answer & explanation
Correct answer: option 4
We know that,
Perimeter of the rectangle = 2 (length + breadth)
Area of the rectangle = Length × Breadth
Given,
Ratio of perimeter and length of a rectangle = 8 : 1
Area of rectangle = 1323 cm2
Let the ratio of perimeter and length of a rectangle = 8a : a
Let length = a, then
2 × (a + breadth) = 8a
= a + breadth = 4a
= breadth = 4a - a
= breadth = 3a
Area of the rectangle = 1323
= a × 3a = 1323
= a2 = 441
= a = 21