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The area of circle is 100 times the area of another circle. What is the ratio of their circumferences? |
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Answer» Let the area of the circles be A1 and A2 and their circumference be c1 and c2 respectively. According to the question it is clear that A1 = 100 A2 ⇒ π (r1)2 = 100 × π (r2)2 ⇒ r1 = 10 r2 ⇒ r1/r2 = 10/1 … (i) Finding the ratios of the circumference; C1: C2 = 2πr1: 2πr2 C1/C2 = (2πr1)/ (2πr2) C1/C2 = r1/r2 Putting the value of r1/r2 from equation (i) C1/C2 = 10/1 C1: C2 = 10: 1 Hence, the ratio of their circumferences is 10: 1. |
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