1)Transfomati in secunde: a)2/5 min =2/5 min ×60 sec/min= 24 sec b)3/4 min =3/4 min ×60 sec/min=45 sec c)7/30 min =7/30 min ×60 sec/min=14 sec d)11/12 min =11/12 min ×60 sec/min=55 sec e)13/5 min =13/5 min ×60 sec/min=156 sec f ) 1/60 min =1/60 min ×60 sec/min= 1 sec
2)Transformati in min. : a) 2/3 h=2/3 h×60 min/ora= 40 min b)1/5 h=1/5 h×60 min/ora= 12 min c)7/12 h=7/12 h×60 min/ora= 35 min d)19/20 h=19/20 h×60 min/ora= 57 min e)7/30 h=7/30 h×60 min/ora= 14 min f)31/60 h=31/60 h×60 min/ora= 31 min