Question 1161710
A distance {{{x}}} on the map (in cm) translates into an actual horizontal distance (in m) of
{{{x*(1km/"2 cm")*(1000m/"1 km")=500x}}}
Antonio can go up from one contour line on the map to the next
over a path with a distance {{{x}}} if
{{{25/500x<=0.3}}} --> {{{x>=25/(500*0.3)}}}{{{cm}}} --> {{{highlight(x>=0.17cm)}}} (1.7mm).
(I rounded that result because I assume Antonio cannot see the difference between 1.7mm and 1.66666...mm).
if Antonio wants to follow an uphill path with a distance between contour lines of 0.2cm (2mm) he will be going up {{{25m}}}, over a horizontal distance of
{{{0.2cm*(1km/"2 cm")*(1000m/"1 km")=100m}}} .
That corresponds to a gradient of {{{25m/100m=0.25}}} ,
Antonio can cycle up that path.
 
When going downhill the {{{x}}} (in cm) should satisfy
{{{25/500x<=0.5}}} --> {{{x>=25/(500*0.5)}}}{{{cm}}} --> {{{highlight(x>=0.10cm)}}} (1.0mm).