Question

Задача ниже!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Answer 1

1) vcp=(s1+s2)/(t1+t2)
s1=s2=s/2
t1=s1/v1
t2=s2/v2
vcp=2*v1*v2/(v1+v2)=2*80*40/(80+40)=53.3 км/ч
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2) s1=v1*t/2
s2=v2*t/2
vcp=(v1+v2)/2=(80+40)/2=60 км/ч
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