What was the American pop rock duo Hall & Oates first US number one hit?

Daryl Hall and John Oates, often referred to as Hall & Oates, are an American pop rock duo. Daryl Hall is generally the lead vocalist; John Oates primarily plays electric guitar and provides backing vocals. The two write most of the songs they perform, separately or in collaboration. They achieved their greatest fame from the late 1970s to the mid-1980s with a fusion of rock and roll and rhythm and blues.

"Sara Smile" became their first Top 10 hit, reaching No. 4 on the Billboard Hot 100 chart in June 1976. "She's Gone," re-released by Atlantic Records after "Sara Smile," also went to the Top 10, reaching No. 7 in October 1976. Hall and Oates followed those hits with the more pop-oriented album "Bigger Than Both of Us" later that year. Though the album's first single (the Philadelphia soul-oriented ballad "Do What You Want, Be What You Are") barely made the Top 40, their second single, "Rich Girl," was a smash. The song was Hall and Oates' first No. 1 hit, reaching the top spot for the week ending March 26, 1977.

The song's lyrics are about a spoiled girl who can rely on her parents' money to do whatever she wants. The song was rumored to be about the then-scandalous newspaper heiress Patty Hearst. In fact, the title character in the song is based on a spoiled heir to a fast-food chain who was an ex-boyfriend of Daryl Hall's girlfriend, Sara Allen. "But you can't write, 'You're a rich boy' in a song, so I changed it to a girl," Hall told 'Rolling Stone'.