Question 14
Il piccolo Marco comes out and climbs on a piano all'altro the mobile scale of a shopping center, one scale there. Proceed in the direction of the scale at constant speed according to this (the interval of time between one step and the other is constant), calpesta 15 steps, proceed in the opposite direction (with the interval of time between one step and the other) and calpesta 35. Quanti scalini calpesterebbe Marco in the passare Does a piano all'altro se la scala mobile fosse ferma?