The area of a circular path enclosed by two concentric circles is 3080 m². If the difference between the radius of the outer edge and that of inner edge of the circular path is 10 m, what is the sum (in m) of the two radii?
(Take π = 227)
Explanation:
Let the radius of the outer circle and inner circle are r0 or ri respectively.
The difference between the radius of the outer edge and that of inner edge of the circular path is 10 m.
r0 - ri = 10 ....(1)
The area of a circular path enclosed by two concentric circles is 3080 m².
⇒ 227r02 - 227ri2 = 3080
⇒ (r0 + ri) (r0 - ri) = 140 × 7
⇒ (r0 + ri) (10) = 140 × 7
⇒ (r0 + ri) = 98
Sum of the two radii = 98 m
Hence, the correct answer is Option D
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