Answer:
Amanda
Step-by-step explanation:
Find the unit rate in each case and then compare the two rates:
4.5 km
-------------- = 1/2 km/min (Sam)
9 min
3.6 km
-------------- = 0.6 km/min (Amanda)
6 min
Amanda, riding at 0.6 km/min, can go further in 1 minute than Sam, who rides at 0.5 km/min.