An element found in another galaxy exists as three isotopes….

An element found in another galaxy exists as three isotopes. Measurements indicate that 15.0% of the atoms have an atomic mass of 83.00 amu, 82.0% have an atomic mass of 84.00 amu, and the other 3.0% have an atomic mass of 82.00 amu. Based on the approximate atomic mass of the element, what is the element?