Aguilera rocked the carpet in a tight pink mini dress, which revealed her new fit figure, Us magazine reported.
The 32-year-old singer, who looked tan, wore her long blonde hair down in loose waves.
A source told the publication that Aguilera has managed her slim-down with a combination of healthy eating and working out.
She earlier made headlines after she debuted an estimated 20-pound weight loss on the show’s season four finale on June 18.
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