Answer
$28.5$ cm/s
Work Step by Step
Average velocity : $v_{avg}=\displaystyle \frac{\Delta x}{\Delta t}=\frac{x_{2}-x_{1}}{t_{2}-t_{1}}$
Instantaneous velocity: $v(t)=\displaystyle \frac{d}{dt}x(t)$
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$v_{avg}=\displaystyle \frac{\Delta x}{\Delta t}=\frac{x_{2}-x_{1}}{t_{2}-t_{1}}=\frac{50.25cm-21.75 cm}{3.00s-2.00s}$
$=28.5$ cm/s
