lexo dit exprimer en fraction d"heure a)55minutes b)45secondes c=12minutes et 15seconde 2) simplifier les écritures obtenues le plus possible jkapte rien help
55 minutes = 55/60 h
= 11/12 h
45 secondes = 45/3600 h
= 1/80 h
12 minutes = 12/60 h
= 1/5 h
15 secondes = 15/3600 h
= 1/240 h