Make the table 750 wide does not mean it's gonna end up 750 wide
If you throw 4 200x200 images in a 750 wide table, you'll get a table that's over 750.
If you make the cell padding or spacing too big, you're go over 750.
If you put 3 cells in there that are 275 wide each, you'll go over 750.
If you put a border on the table that's 5 pixels big, you'll go over 750.
Be careful