Răspuns :
100 m = 40 sec. 50 m = 40 : 2 = 20 sec ( e jumatate din drum ) .25 de m = 20 : 2 = 10 sec ( un sfert ). 125 m = 40 + 10 = 50 sec
Mai simplu,
100 ................40
125..................x
100/125=40/x
x=125 ori 40/100
x=50
100 ................40
125..................x
100/125=40/x
x=125 ori 40/100
x=50