A carpet of size 5 m x 2 m has 25 cm wide red border. The inner part of the carpet
is blue in colour. Find the area of blue portion. What is the ratio of the areas of red
portion to blue portion?
Answers
13:27
Convert all into cm:
5m = 500 cm
2m = 200 cm
Area of the whole carpet = 500 x 200 = 100 000 cm²
Find Length and breadth of the blue portion:
Length = 500 - 25 - 25 = 450 cm
Breadth = 200 - 25 - 25 = 150 cm
Find area of the blue portion:
Area = Length x Breadth
Area = 450 x 150 = 67500 cm²
Find the area of the red portion:
Area = 100 000 - 67500 = 32500 cm²
Ratio of the red portion to blue portion:
Red : Blue = 32500 : 67500 = 13 : 27
Convert all into cm:
5m = 500 cm
2m = 200 cm
Area of the whole carpet = 500 x 200 = 100 000 cm²
Find Length and breadth of the blue portion:
Length = 500 - 25 - 25 = 450 cm
Breadth = 200 - 25 - 25 = 150 cm
Find area of the blue portion:
Area = Length x Breadth
Area = 450 x 150 = 67500 cm²
Find the area of the red portion:
Area = 100 000 - 67500 = 32500 cm²
Ratio of the red portion to blue portion:
Red : Blue = 32500 : 67500 = 13 : 27