Abrand of cereal had 1.21.2 1.2 1, point, 2 milligrams (mg)(\text{mg}) (mg) left parenthesis, start text, m, g, end text, right parenthesis of iron per serving. then they changed their recipe so they had 1.8 mg1.8\,\text{mg} 1.8mg 1, point, 8, start text, m, g, end text of iron per serving. what was the percent increase in iron? %\% %