You have probably heard the saying, "Muscle weighs more than fat." While a pound of muscle weighs the same as a pound of fat, the volume is different. Muscle is denser than fat.
A pound of fat will take up about 18% more space then a pound of muscle. If squeezed into cans, you would need a can 18% bigger to contain the pound of fat.
In addition to volume differences, keep in mind that muscle wraps tightly to the skeletal structure whereas fat hangs loosely. So, all total, you can find two people of the same build and height who weigh the same appearing vastly different based on their lean body mass (LBM).
If your goals are to improve your physical appearance, you should concern yourself more with where your LBM is rather than your body weight.