If you started a walk at 2:43pm and ended it at 5:18pm how long would it be?
2:43 PM to 3 PM = 17 minutes
3PM to 5 PM = 2 hours
5 PM to 5:18 PM = 18 minutes
2 hours + 17 minutes + 18 minutes =
2 hours 35 min
Elaborating on CPhill's answer...
See that 2:43PM to 3PM is just 2:43PM to 2:59PM, with one extra minute. We can do this to avoid confusion. This is simple. \(59-43=16\), and \(16+1=17\). Therefore, the time from 2:43PM to 3PM is 17 minutes long.
3PM to 5PM is simple - we see there are \(5-3=2\) hours between the times. This accounts for \(2\times 60=120\) minutes between 3PM to 5PM, because 60 minutes make up an hour.
Finally, we can see that 5PM to 5:18PM is simply 18 minutes.
Adding all the minutes up, we get \(17+120+18\) total minutes walking and that equals \(155\) minutes. This is also equal to 2 hours 35 minutes.
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