title: VS2010 Unit test fails while result is correct
body: <p>I've made a demo project on testing with VS2010 at the company I work at.
  As input for the tests a little math calculation class: MathOps.
  MathOps can throw some exceptions and whatnot.
  However, when I was setting up the unit tests I came acrosse a unit test which seems to behave very oddly.</p>
  
  <p>The MathOps object is called target and is initialized in a test initialization method to demonstrate what it might be used for.</p>
  
  <pre><code>Private target As MathOps = Nothing
  
  &lt;TestInitialize()&gt; _
  Public Sub MyTestInitialize()
      target = New MathOps()
  End Sub
  </code></pre>
  
  <p>The test which is misbehaving is the following one:</p>
  
  <pre><code>'''&lt;summary&gt;
  '''A test for MathOps.add
  '''&lt;/summary&gt;
  &lt;TestMethod()&gt; _
  Public Sub addTest()
      Dim first As Double = 2.3
      Dim second As Double = 3.4
      Dim expected As Double = 5.7
      Dim actual As Double
      actual = target.add(first, second)
      Assert.AreEqual(expected, actual)
  End Sub
  </code></pre>
  
  <p>When I use addition terms which result in 5.7 being the expected/result value, the assertion fails, even though the code produces the right result.</p>
  
  <blockquote>
    <p>Assert.AreEqual failed. Expected:&lt;5,7>. Actual:&lt;5,7>.</p>
  </blockquote>
  
  <p>If I make it 5.7000001 by adding 3.4000001 instead of 3.4 the test passes.</p>
  
  <p>Does anyone know the cause of this error?</p>