In two very famous arias ( Rodolfo 's `` Che gelida manina â '' What a cold little hand '' and Mimi 's `` SÃ , mi chiamano MimÃ â '' Yes , they call me MimÃ '' ) , they tell each other about their different backgrounds . In two arias ( Rodolfo 's Che gelida manina -- `` What a cold little hand '' and MimÃ 's SÃ , mi chiamano MimÃ -- `` Yes , they call me MimÃ '' ) , they tell each other about their different backgrounds .