Dynamically setting the location of the Controls

Question

I am trying to add controls dynamically in C#.net. But one control i.e. combobox has location as 95,87 is located at the top of the window whereas the other control i.e. textbox having location 95,87 is located at the bottom of the window.Also textbox is added into groupbox which has location as 1,512. Why both controls having same location are displayed in different parts of the window?