You can put this solution on YOUR website! If an object travels at a speed of 3 meters per second, how many meters does it travel in half an hour?
distance = rate*time
d = rt
convert 3 m/sec to m/hour
3 m/sec * 60 sec/min * 60 min/hr = 10800 m/hr
.
d = 10800 m/hr * .5 hour
d = 5400 meters