[tex]dane:\\\lambda = 0,060 \ km = 60 \ m\\n = 20\\t = 4 \ min = 4\cdot 60 \ s = 240 \ s\\szukane:\\v = ?\\\\Rozwiazanie\\\\v = \frac{\lambda}{T}\\\\ale \ \ T = \frac{t}{n} = \frac{240 \ s}{20} = 12 \ s\\\\v = \frac{60 \ m}{12 \ s} = 5\frac{m}{s}[/tex]
Odp. Szukana prędkość v = 5 m/s.