Sum of perimeter of two rectangles is 248 cm and breadth of both rectangles is equal to radius of circle whose circumference is 44 cm. If length of both rectangles is in the ratio of 9 : 13, then find the difference between areas of both rectangles?
Sum of perimeter of two rectangles is 248 cm and breadth of both rectangles is equal to radius of circle whose circumference is 44 cm. If length of both rectangles is in the ratio of 9 : 13, then find the difference between areas of both rectangles? Correct Answer 140 cm
GIVEN :
Sum of perimeter of two rectangles is 248 cm
Circumference of circle = 44 cm
Ratio of lengths of both the rectangles = 9 : 13
FORMULA USED :
Circumference of circle = 2πr
Perimeter of rectangle = 2 × (length + breadth)
Area of rectangle = length × breadth
CALCULATION :
Let the length of rectangles be 9x and 13x
Circumference of circle = 2πr = 44
⇒ r = 7
Breadth of rectangle = radius of circle
According to question,
Sum of perimeter of two rectangle = 248 cm
⇒ 2 (9x + 7) + 2 (13x + 7) = 248
⇒ 18x + 14 + 26x + 14 = 248
⇒ 44x + 28 = 248
⇒ 44x = 220
⇒ x = 5
⇒ Length of rectangles = 9 × 5 = 45 cm and 13 × 5 = 65 cm
⇒ Difference between areas = 65 × 7 – 45 × 7 = 140 cm2
∴ Required difference = 140 cm2