Why `float:left` doesn't work with a fixed width?

Question

I have two divs on a webpage and I would like both of them to have a fixed width and would like the first div to be floated to the left of the second div.

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Answer 1

Float both divs left.

Apply a positive left margin of width(div.right), in your case 200px.

Apply a negative left margin of width(div.left) + width(div.right), in your case, 200px + 200px = 400px.

div.left { float: left; width: 200px; margin-left: 200px; }
div.right { float: left; width: 200px; margin-left: -400px; }