Mentors to duet with 'X Factor' finalists

The 'X Factor' finalists are set to duet with their mentors at this weekend's final.

Amelia Lily will sing Ike and Tina Tuner's 'River Deep, Mountain High' with judge Kelly Rowland, and girl group Little Mix and their mentor Tulisa Contostavlos are set to perform a medley of Alicia Keys hits 'If I Ain't Got You' and 'Empire State of Mind' at London's Wembley Arena in front of 10,000 fans.