a. Thời gian:
\(t_1=\dfrac{s_1}{v_1}=\dfrac{80}{35}=\dfrac{16}{7}h\)
b. Vận tốc trung bình:
\(v_{tb}=\dfrac{s_1+s_2}{t_1+t_2}=\dfrac{80+15}{\dfrac{16}{7}+\dfrac{20}{60}}\approx41\left(\dfrac{km}{h}\right)\)
a. Thời gian:
vtb=s1+s2t1+t2=80+15167+2060≈41(kmh)