Find the Start Time
Free printable find the start time worksheets. A blank clock, a duration, and the end time shown - work backwards to the start. With a key.
Six problems a sheet, each showing a blank clock, the length of time that passed, and a second clock set to the time it finished. The student counts backwards to work out when it began. Of the three elapsed-time questions this is reliably the hardest: counting back over an hour boundary catches people out in a way counting forwards does not.
Times sit on five-minute steps and both clocks stay on the same twelve-hour face. The duration is printed between the two clocks because the question gives it to you - what is missing is the time, not the gap.
What this worksheet covers
- Find when something started from its end time and how long it took
- Count backward in hours and minutes
Common Core standards
- 3.MD.A.1 Tell time to the nearest minute and solve problems about time intervals in minutes.
Frequently asked questions
How do you find the start time?
Count backwards from the end time by the duration - take off the hours first, then the minutes. Ending at 5:45 after 2 hours 10 minutes gives 3:45, then 3:35.
Why is working backwards harder?
Subtracting minutes often crosses an hour boundary the wrong way. Taking 20 minutes off 3:10 means borrowing an hour to reach 2:50, which is the step most often got wrong.
Is the duration given on the sheet?
Yes, printed between the two clocks. The question gives you the gap and the finishing time; the starting time is what is missing.
Is there an easier version?
Find the End Time works forwards from a start time, and the Elapsed Time page gives both times and asks only for the gap between them.