If a circular paper disc is trimmed in such a way that its circumference is reduced in the ratio 2:5, In what ratio is the surface area reduced?
-
A.
8 : 125 -
B.
2 : 5 -
C.
8 : 25 -
D.
4 : 25 -
E.
4 : 10
Correct Answer: Option D
Explanation
If the circumference of the circular Fig. paper disc is reduced in the ratio 2 : 5, then the surface area must be reduced by ratio 22 : 52
= 4 : 25