VB.NET此程序输出

Question

Dim k As Double
    For k = 1.0 To 2.0 Step 0.2
        MsgBox(k)
    Next
    MsgBox(k)

该程序给出2.2输出，为什么以下程序给出2.1输出作为输出

Dim k As Double
    For k = 1.0 To 2.0 Step 0.1
        MsgBox(k)
    Next
    MsgBox(k)