Problem
The sloped parts total 1 + 1 + 1 = 3 squares of moving; the 3 flat squares are stops and do not count.
A rising line means distance is changing, so he is riding only there.
5.MD.B.2Draw A DiagramThe time Owen spends moving is exactly the three sloped grid squares on the graph, one for each riding stretch, so the moving time is three squares.
The line's height is Owen's distance from home, so a stretch where the line rises is a stretch where that distance is growing, and his distance from home can grow only while he is actually riding.
Being farther from home than a moment earlier means his distance now is the earlier distance plus the new ground he covered, so that extra ground had to be crossed by moving.
Where the line is flat his distance from home is the same as just before, so he covered no new ground and that flat time adds nothing to the moving total.
There are three separate rising stretches, each one grid square wide, and the whole moving time is just those riding stretches joined together.
Joining the moving stretches with no gaps and no overlaps rebuilds the whole moving time, so their square-counts add up: one and one and one.
Each square is 15 minutes, so 3 moving squares = 3 x 15 = 45 minutes.
Multiplying square-count by minutes-per-square gives total moving time in the right unit.
4.MD.A.2Analyze The UnitsOn a time-distance graph the slanted parts are when you're moving - count those squares and turn them into minutes!