The sum of the circumference of the two circles is 78.5cm. The radius ratio of the big circle to the small circle is 3:2. What is the area of the big circle

The sum of radius of big circle and small circle is: 78.5 △ 3.14 △ 2 = 12.5cm
3+2=5
The radius of the great circle is 12.5 × 3 / 5 = 7.5cm,
The area is: 3.14 × 7.5 × 7.5 = 176.625 square centimeter

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