Thread: area and circumference

Hi all,
i am not able to get the relation between area and circumference in the given below.could any one please help me out


If the circumference of a circle is decreased by 50% then the percentage of decrease in its area is?


Regards
Padma

Circumference = 2*pi*r which can be rewritten as r= C/(2*pi)
Area = pi*(r^2)
substitute with 50% of C
pi * ((1/2)(1/(2*pi))^2

What is your coefficient ?

Originally Posted by Padma

Hi all,
i am not able to get the relation between area and circumference in the given below.could any one please help me out


If the circumference of a circle is decreased by 50% then the percentage of decrease in its area is?


Regards
Padma

If you magnify the length of a shape by a scale factor , then the area is magnified by .

In this case, the length scale factor .

So what is the area scale factor?