To compare their speed (rate), we need to have the same time or same distance to use as a reference.
Matt ran 50 meters per 10 seconds. Molly ran 30 meters per 5 seconds. If she ran for 5 more seconds, she would have gone 30 more meters, for 30 meters per 10 seconds. Thus, Molly went faster.
Alternately, you could calculate their speeds in meters per (one) second and compare. 50 meters per 10 seconds is 5 meters per second, and 30 meters per 5 seconds is 6 meters per second.
Answer: 100 ml each hour.
Step-by-step explanation:
1000 -400 =600 used from original amount.
Divide 600/6 = 100 ml per hour.
