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Task/Averages-Arithmetic-mean/Wren/averages-arithmetic-mean.wren

@@ -0,0 +1,7 @@
+class Arithmetic {
+    static mean(arr) {
+        if (arr.count == 0) Fiber.abort("Length must be greater than zero")
+        return arr.reduce(Fn.new{ |x,y| x+y }) / arr.count
+    }
+}
+Arithmetic.mean([1,2,3,4,5]) // 3