Find the perimeter of a rectangle whose length and breadth are 15.4 cm and 11.6 cm respectively.
| Length of the rectangle | = | 15.4 cm |
| Breadth of the rectangle | = | 11.6 cm |
| Perimeter of the rectangle | = | 2(l + b) units |
| = | 2(15.4 + 11.6) cm | |
| = | (2 × 27) cm | |
| = | 54 cm | |
| Hence, the perimeter of the rectangle is 54 cm. | ||
Find the cost of fencing a rectangular field 260 m long and 175 m wide at Rs. 40 per metre.
| Length of the field | = | 260 m |
| Breadth of the field | = | 175 m |
| Perimeter of the field | = | 2(l + b) units |
| = | 2(260 + 175) m | |
| = | (2 × 435) m | |
| = | 870 m | |
| Cost of fencing per metre | = | Rs. 40 |
| Total cost of fencing | = | Rs.(870 × 40) |
| = | Rs. 34800 |
The length and the breadth of a rectangular field are 240 m and 180 m respectively. It is fenced with three rounds of a rope. Find the length of the rope.
| Length of the field = 240 m and its breadth = 180 m | ||
| Perimeter of the field | = | 2 × (length + breadth) units |
| = | {2 × (240 + 180)} m | |
| = | (2 × 420) m | |
| = | 840 m | |
| Total length of the rope | = | (3 × 840) m |
| = | 2520 m | |
The length and the breadth of a rectangle are in the ratio 3 ∶ 2. If its perimeter is 1 m 40 cm, find its dimensions.
| Let the length of the rectangle be 3x cm. | ||
| Then, its breadth | = | 2x cm. |
| ∴ Perimeter of the rectangle | = | {2 × (length + breadth)} units |
| = | {2 × (3x + 2x)} cm | |
| = | (2 × 5x) cm | |
| = | (10x) cm | |
| Given, perimeter of the rectangle | = | 1 m 40 cm |
| = | 140 cm | |
| ∴ 10x | = | 140 |
| ⇒ x | = |  |
| ⇒ x | = | 14 |
| ∴ Length = (3 × 14) cm = 42 cm and breadth = (2 × 14) cm = 28 cm. | ||
Find the perimeter of a square, each of whose sides measures 3.6 cm.
| Each side of the square | = | 3.6 cm |
| Perimeter of the square | = | (4 × side) |
| = | (4 × 3.6) cm | |
| = | 14.4 cm |