10. Chester Arthur
Source: Wikipedia.
Chester Arthur succeeded James Garfield as America’s 21st president after Garfield was assassinated in 1881. He had an IQ of 148, according to Simonton’s estimates.
Arthur graduated from Union College in 1848 and practiced law in New York City before being elected vice president on the Republican ticket in 1880. When he assumed the presidency a little over a year later, he distinguished himself as a reformer and devoted much of his term to overhauling the civil service.