Answer:
v = 172 km/h
Explanation:
For the first 12 hours, it traveled at an average speed of 185 km/h. Let d₁ is distance. So,
[tex]d_1=v_1\times t_1\\\\d_1=185\ km/h\times 12\ h\\\\d_1=2220\ km[/tex]
For the next 13 hours, it traveled at an average speed of 160 km/h. Let d₂ is the distance. So,
[tex]d_2=v_2\times t_2\\\\d_2=160\ km/h\times 13\ h\\\\d_2=2080\ km[/tex]
Average speed = total distance/time taken
So,
[tex]v=\dfrac{d_1+d_2}{t_1+t_2}\\\\v=\dfrac{2220+2080}{12+13}\\\\v=172\ km/h[/tex]
So, the average speed of the whole journey is 172 km/h.
