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How to Tell the Amount of Elasped Time

Determining the elapsed time or expected elapsed time is important in many areas of living. In baking a cake or a roast, recipes give a certain amount of time that the item should cook. If you put something in the oven at 10:30 am and it's supposed to cook for forty five minutes you need to be able to calculate what time you should take it from the oven.

Instructions

- 1
  Write down the ending time for the timed event you are calculating.
- 2
  Write down the beginning time underneath the ending time. For example: an ending time of 5:30 pm and a beginning time of 1:30 pm.
- 3
  Subtract the 2 numbers. The result is the number of hours and minutes that have elapsed since 1: 30 pm, which is 4 hours in this example.
- 4
  Calculate elapsed time when there are odd times such as a start time of 5:35 and an end time of 9:20 by subtracting the 5:35 from the 9:20.
- 5
  Change the resulting sum into hours and minutes. The result of 3.85 equals 3.8 hours or 3 and 3/4 hours. So the elapsed time is 3 hours and 45 minutes. A calculator can also be used to do the subtraction.

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