It is evening 7:15. What time would it be 10 hours earlier?

Jessica
Fourth grade

Hi Jessica,

This is a place where I think it is reasonable to just count. Take a piece of paper and write a column if times, going backwards in steps of one hour from 7:15 in the evening. Just remember that an hour before 1:15 is 12:15.

Now count. From 7:15 to 6:15 is one hour. Fron 6:15 to 5:15 is one hour.... So what time is it after you have counted backwards for 10 hours? Is it in the morning or evening?

There is however an easier way to do this. Since my clock works in 12 hour cycles, 12 hours from now it will read exactly the same as it does now. Thus 12 hours before it read 7:15 it also read 7:15. Hence 2 hours after that, which is 10 hours ago it read 9:15. Is that in the morning or afternoon?

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