Pave a 2-meter-wide path around a 37.68-meter-long circular pool. How many square meters is the area of the path?
The radius of the small circle: 37.68 ÷ (2 × 3.14) = 37.68 ÷ 6.28 = 6 (m); the radius of the big circle: 6 + 2 = 8 (m); the area of the small road: 3.14 × (82-62) = 3.14 × (64-36) = 3.14 × 28 = 87.92 (M2); a: the area of the small road is 87.92 m2
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