To find out how many steps Mario walked per hour, you can divide the total number of steps by the total number of hours.
Mario walked 6,000 steps in 12 hours.
So, the calculation is:
\[ \text{Steps per hour} = \frac{\text{Total steps}}{\text{Total hours}} = \frac{6000}{12} = 500 \]
Mario walked 500 steps per hour.