Question

2 h 30 min 45 s-1 h 45 min 55 s=

Answer 1

 2h 30 min  45 sec

- 1h 45 min  55 sec

1 h = 60 minute

1 min = 60 sec

2h 30 min 45 sec = > 1h ( 2-1) 89 min ( 30 + 60 - 1)  105 sec ( 60 + 45)

putem scrie astfel :

 1 h  89 min  105 sec

 1 h  45 mn     55 sec

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       44 min     50 sec