The circumference of a semicircle is 15.42 meters, and its radius is______ Rice

Let the radius of a circle be r m, then 2 × 3.14r △ 2 + 2R = 15.42 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 3.14r + 2R = 15.42 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 5.14r = 15.42 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp

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