\(V_{tb}=\frac{S}{t}=\frac{S}{t_1+t_2}\)
\(=\frac{S}{\frac{S}{4.16}+\frac{3S}{4.20}}\)
\(=\frac{S}{S\left(\frac{1}{64}+\frac{3}{80}\right)}\)
\(=\frac{1}{\frac{1}{64}+\frac{3}{80}}\)
\(=18,82\left(km/h\right)\)
vtb=\(\frac{s}{\frac{0.25s}{16}+\frac{0.75s}{20}}=\frac{1}{\frac{0.25}{16}+\frac{0.75}{20}}\approx18.823\)
Trả lời nhanh giúp mình với 😙