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

It seems to me that it is the simple rule that blocks, unless floated, always start a new line. w3.org/TR/CSS2/visuren.html#block-formatting section 9.4.1 –