Odpowiedź:
t1 = 15 min = 1/4 h
v1 = 4 km/h
t2 = 1 h
v2 = 10 km/s
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vśr ?
s1 = V1*t1 = 4 km/h * 1/4 h = 1 km
s2 = v2*t2 = 10 km/h * 1 h = 10 km
s = s1+s2 = 1km+10km = 11 km
t = t1+t2 = 1/4h+1h = 1 i 1/4 h
vśr = s/t = 11km / 1 i 1/4 h = 11 km / 5/4 h = 11* 4/5 = 44/5 = 8 i 4/5 = 8,8 km/h
vśr = 8,8 km/h
Wyjaśnienie:
