Area of a circle is directly proportional to the square of radius of the circle while the circumference is proportional to the radius of the circle. This means that if the radius of a circle is increased x times, then its area will be increased to x^2 times the original area, and the circumference will increase to x times the original circumference.
Thus when the radius is doubled, or in other words if radius mad 2 time the original radius, the area of circle will become 2^2 = 4 time the original area. The circumference will become 2 times the original circumference.
We can calculate exact area and circumference of a circle from its radius using the following equations:
Area of circle = (pi/4)*r^2
Circumference of circle = 2*pi*r
Where r is the radius of the circle.
I know this is a lot, sorry.
Answer:
one solution
Step-by-step explanation:
Answer:
1530cm
Step-by-step explanation:
First figure (9x10)x9=810
Second figure (18x10)x4=720
720+810=1530
Answer:
Step-by-step explanation:
"At least" is inclusive, so you can be 21 years old.
