update

src/test/java/rocks/zipcode/quiz5/fundamentals/calculator/AddTest.java

         Double actual = calculator.add(input1, input2);
 
         // then
-        Assert.assertEquals(expected, actual, 0);
+        Assert.assertEquals(expected, actual, 0.01);
     }
 }

src/test/java/rocks/zipcode/quiz5/fundamentals/calculator/SquareTest.java

         Double actual = calculator.square(input);
 
         // then
-        Assert.assertEquals(expected, actual, 0);
+        Assert.assertEquals(expected, actual, 0.01);
     }
 }