# If an object is moving at 3 m/s and accelerates to 51 m/s over 12 seconds, what was the object's rate of acceleration?

$4 \frac{m}{s} / s$
$a = \frac{\Delta v}{\Delta t} = \frac{51 \frac{m}{s} - 3 \frac{m}{s}}{12 s} = \frac{48 \frac{m}{s}}{12 s} = 4 \frac{m}{s} / s$