Answer:
His average speed was 0.144km/min
Step-by-step explanation:
At first Steve traveled 12 kilometers for 52 minutes, therefore his speed was
[tex]12km/52min=0.2308km/min[/tex]
On his return journey he travels the same distance but in 3 hours 24 minutes or in 204 minutes; therefore his speed during his return journey was
[tex]12km/204min=0.0589km/min[/tex]
So his average speed during his trip was just the average of these two speeds:
[tex]S_{avg}=\frac{0.2308+0.0589}{2} =\boxed{0.1448km/min}[/tex]
