Average velocity is given by the change in position divided by the change in time: change in‘d’ divided by change in‘t’. That is, the final position minus the initial position divided by the final time minus the initial time. That equals negative four point two centimeters as the final position minus three point four centimeters for the initial position divided by six point one seconds minus three point zero seconds. This gives the average velocity as negative two point five centimeters per second. The negative sign is probably thought of as meaning it’s going backwards.