[JLMounce]

As SRGN pointed out, the middle number is the aspect ratio and is simply a percentage of section width. As a result, it's possible and sometimes common to have a smaller aspect ratio tire in the rear. This typically happens if the tire in the rear is wider than the tire in the front.

In your case, the front tire is 11.25mm taller than the rear tire since both have the same section width.

Did you purchase these wheels and tires, or did you purchase the car with them already on it. From an aesthetics purpose, you're correct that this type of tire sizing you'd typically see the taller tire on the rear. You also note that you have rubbing issues in the rear. Is it possible the previous person that sourced these wheels and tires and done so with the intention of running the taller tire in the rear, but due to rubbing issues, swapped the wheels? Another possibility is than a tire rotation was done by somebody that didn't bother to look to see that there were staggered tire sizes.

What kind of car are these wheels on? A 225 section width tire on an 8" wheel is a bit narrow. I don't think it'd try to stretch a 215 on to an 8" wheel. That's a size more suited for a 6 or 7" wheel.

I'd pull a front and rear wheel off the car and look at the back of the spokes or the hoop. The wheel specs are often found there. You might find something like 17x8 0ET, which would be an 8" wide wheel with a 0 offset, or 4.5" backspace. Remember that wheel width is measured from the inside of the bead seats. An 8" wide wheel typically measured 9" from outside lip to outside lip.

Once you know what actual size and offset your wheels are, you can make some better informed choices. On many of these cars an 8" wheel with a 4.5" backspace has the wheel sitting too far to the outside of the car, and tire contact with the wheel well can happen. As widths get wider, you typically want to see something like a +4 to +8 offset to move the wheel inward. In depends on the car though and why measuring is important.

Have you considered cutting, or rolling the fenders if the rub is minor? That may also allow you to get the front wheel and tire on the back where it likely belongs.