Subtract the end time from the start time.

For example, Xiaoming left home at 7: 30 in the morning and arrived at school at 8: 20. How long does it take Xiaoming to get from home to school?

As the title, the end time is 8:20 and the start time is 7:30, so it can be listed. As can be seen from the formula, there is not enough time in the minute position, so we need to borrow one forward, and 1 hour is equal to 60 minutes.

Therefore, it can be concluded that it takes Xiao Ming 50 minutes to get from home to school.

Extended data

The calculation of time is divided into calculation time: the unified timing method adopts the way of tail+head.

Expression: When and when.

Calculation period: unified timing method adopts head-to-tail calculation.

Expression: a few hours and minutes.

Different representations represent different results.

For example:

Time after 9: 00 am 15 minutes (calculation time): 9: 00 am 15 (9: 15).

How long does it take from 9:00 am to 10:30 am (time period): 1 hour 30 minutes.

Time learning

Objectives: ① Combining with real life, we can understand the schedules of work and rest in different areas, look at the schedules and get the necessary information from them. (2) Be able to make a timetable independently and master the basic methods of making a timetable.

Point: Use the 24-hour timing method to calculate the time taken to solve the problem.

Difficulties: Make a reasonable timetable independently.

Breakthrough: observe the characteristics of the timetable and find out how to make it.

I. 24-hour timing mode:

One day =24 hours (twice clockwise)-the first lap: from 12 pm to12pm; The second lap: noon 12 to afternoon 12.

Midnight 12 =0.

Second, the formula:

End Time-Start Time = Elapsed Time

End Time-Elapsed Time = Start Time

Start Time+Elapsed Time = End Time