Daily Value of Iron?

Ok, so, I know babies 7-12 months of age need about 11mg of iron a day. But my question is, on adult food (like a package of grits) it only shows the percentage, not the actual amount in mgs. And that percentage is based off an adults need of 18 mgs a day. So if something has %45 of the DV of iron that an adult needs, what does that amount to for an infant? I'm horrible at math.