Elapsed Time with Regrouping
Remember: 1 hour = 60 minutes
Add without regrouping:
Maria began soccer practice at 3:30 p.m. She practiced for 1 hour and 45 minutes. At what time did she finish?
3:30
+1:45
4:75 p.m.
+1 -60
5:15 p.m.
Subtracting with regrouping:
Jevon spent 2 hours and 20 minutes working on his report. He finished working at 6:00 p.m. What time did he start?
6:00 5:60
-2:20 - 2:20
3:40 p.m. 3:40 p.m.
If you don't have any minutes to subtract from, the you need to take one hour away and convert it to your minutes.