Advertisements
Advertisements
Question
If the length and breadth of a rectangle are doubled, how many times the perimeter of the old rectangle will that of the new rectangle be?
Advertisements
Solution
 |
 |
| Old rectangle | New rectangle |
Let l be the length of the old rectangle and b be the breadth.
∴ the old rectangle's perimeter = 2(l + b)
new rectangle length = 2l and breadth = 2b
∴ The new rectangle's perimeter = 2(2l + 2b)
= 2 × 2 (l + b)
= 2 × Perimeter of old rectangle
∴ The new rectangle's perimeter will be twice that of the old rectangle.
RELATED QUESTIONS
As shown in the figure, four napkins, all of the same size, were made from a square piece of cloth of length 1 m. What length of lace will be required to trim all four sides of all the napkins?
A page of a calendar is 45 cm long and 26 cm wide. What is its area?
Find the area of a rectangle whose length and breadth are 12 cm and 4 cm respectively.
The area of a rectangular piece of cardboard is 36 sq cm and its length is 9 cm. What is the width of the cardboard?
If the cost of 1 sq m of a plot of land is 900 rupees, find the total cost of a plot of land that is 25 m long and 20 m broad.
What will be the labour cost of laying the floor of an assembly hall that is 16 m long and 12 m wide if the cost of laying 1 sq m is 80 rupees?
A wall of a room is of dimensions 5 m × 4 m. It has a window of dimensions 1.5 m × 1 m and a door of dimensions 2.25 m × 1 m. Find the area of the wall which is to be painted.
A carpet of size 5 m × 2 m has 25 cm wide red border. The inner part of the carpet is blue in colour (see figure). Find the area of blue portion. What is the ratio of areas of red portion to blue portion?
In a park of dimensions 20 m × 15 m, there is a L shaped 1 m wide flower bed as shown in the following figure. Find the total cost of manuring for the flower bed at the rate of Rs 45 per m2.
What unit is used to express the area of a rectangle?
