<prompt> Pamakwikwi eOlympics yeZhizha ya2012 muLondon, Joyce akapedza nguva yemasekonzi 25,28 muHeat 8 yemamita 50 akasununguka  <response>: , achimumanikidza kupinda mumakwikwi ekushambira nemamwe makwikwi maviri nokuda kwenzvimbo yegumi nenhanhatu uye yokupedzisira mumakwikwi e50-metre semi-finals. Akurudzirwa nevanhu vomunharaunda, mukwikwidzi weBritish Amy Smith akakunda kumhanya kwekutanga nenguva ye24.82, achigumisa kutora chikamu kwaJoyce muchiitiko ichi. 