Advertisements
Advertisements
Question
Length of a rectangle is three times its breadth. Perimeter of the rectangle is 40 cm. Find its length and width.
Advertisements
Solution
Let l and b are length and breadth respectively of the given rectangle.
According to question, l = 3b
Perimeter of the rectangle = 2(1 + b)
⇒ 40 cm = 2(3b + b)
⇒ 40 cm = 2 × 4b
⇒ 40 cm = 8b
⇒ `40/8` cm = b
⇒ b = 5 cm
∴ The required length = 3 × 5 cm = 15 cm and breadth = 5 cm
APPEARS IN
RELATED QUESTIONS
In each of the following cases, ABCD is a square and PQRS is a rectangle. Find, in each case, the area of the shaded portion.
(All measurements are in metre).
(i)

(ii)

Each side of a square plot of land is 55 m. Find the cost of fencing the plot at the rate of ₹32 per meter.
Find the perimeter of an equilateral triangle of side 9.8 cm.
An athlete takes 10 rounds of a rectangular park, 50 m long and 25 m wide. Find the total distance covered by him.
A farmer has a rectangular field of length and breadth 240 m and 180 m respectively. He wants to fence it with 3 rounds of rope as shown in the figure. What is the total length of rope he must use?

Each side of a square is 9 m long. Find its perimeter.
The length of a rectangular plot of land is 50 m and its width is 30 m. A triple fence has to be put along its edges. If the wire costs 60 rupees per metre, what will be the total cost of the wire needed for the fence?
A game requires its players to run around a square playground. Each side of the playground is 20 m long. One player took 5 rounds around the playground. How many metres did he run altogether?
Look at the figures on the sheet of graph paper. Measure their sides with the help of the lines on the graph paper. Write the perimeter of each in the right box.

- Perimeter of rectangle ABCD = ______ cm.
- Perimeter of rectangle EFGH = ______ cm.
- Perimeter of square PQRS = ______ cm.
- Perimeter of rectangle STUV = ______ cm.
The length of a rectangle is three times its breadth. If its perimeter is 64 cm, find the sides of the rectangle
