Yihana walks for 10 minutes. A graph of her elevation in metres
versus time in minutes is shown.
The length of time for which she was walking uphill is
, 2022
Pick one
Solution
Yihana is walking uphill exactly when the graph is increasing
(that is, when the slope of the segment of the graph is positive).
This is between 0 and 3 minutes and between 8 and 10 minutes, which
correspond to lengths of time of 3 minutes and 2 minutes in these two
cases, for a total of 5 minutes.
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