7. If a wire of 440 m length is moulded in the form of a circle and a square
find the ratio of the area of the circle to that of square.
Answers
Answer:
14 : 11
Step-by-step explanation:
When it's moulded to a circle (of radius "R")
Length of wire = Circumference of circle
440 m = 2πR
R = 440/(2π) m
R = 220/π m
R = 220/(22/7) m
R = 7 × 220/22 m
R = 7 × 10 m
R = 70 m
Area of circle = πR²
= 22/7 × (70 m)²
= 22/7 × 4900 m²
= 15400 m²
When it's moulded into a square (of side length "a")
Length of wire = Perimeter of square
440 m = 4a
a = 440/4 m
a = 110 m
Area of square
A = a²
= (110 m)²
= 12100 m²
Ratio:
Area of circle / Area of square
= 15400 m² / (12100 m²)
= (14 × 1100 m²) / (11 × 1100 m²)
= 14 / 11
Answer:
14:11
Step-by-step explanation:
Solution:-
Length of wire = 440 m
So, this will be considered as the perimeter for a square and circumference for a circle.
So, according to the question.
Circumference of circle = 2πr
440 = 2*22/7*r
44r = 440*7
r = (440*7)/44
Radius of the circle = 70 m.
Now, area of the circle = πr²
= 22/7*70*7
Area of the circle = 15400 sq m
Now,
Perimeter of the square = 440 m
Each side of square = Perimeter/4
= 440/4
Each side of square = 110 m
Now,
Area of the square = side × side
= 110 × 110
Area of the square = 12100 sq m
Now,
Ratio of the area of the circle to that the area of the square.
= 15400 : 12100
Ratio = 14 : 11
Answer.