The first (wrapper) DIV now has a white background, a width of 99%, a 1-pixel border and no padding.
The height is not defined so it will be that of the highest image (in this example, the middle one).
Inside the wrapper are three left-floating objects (DIV) each with a width of 33.3%
The text is inside its own DIV with some padding and the image also has its own DIV.
The images having a width of 100% will resize automatically to fit the space available.
Because the three floating objects have a width of 33.3%, the gap at the far right is minimal, possibly down to 1 or 2 pixels only. If the combined widths of the various floating DIVS is too much, the last one will overflow onto the next line.