I wish tutors would give more than just the answer.
if 3 cats can catch 3 rats in 3 minutes, how many cats are needed to catch 100 rats in 100 minutes?
Since 3 cats can catch 3 rats in 3 minutes, then each cat catches one rat
in those 3 minutes. So if you have one cat for each rat it doesn't matter
how many you have, as long as you have 1 cat for each rat, each cat will catch
one rat in those 3 minutes, So 100 cats will catch 100 rats in 3 minutes, just
as 1000 cats will catch 1000 rats in 3 minutes.
Edwin