John has 2 hives of bees.  One of the hives has 1000 bees and produces 500 liters of honey.  The second has 20% fewer bees but each bee produces 40% more honey.  How much honey does he produce?
The second hive has 20/100*1000 = 200 fewer bees.
This translates to 1000-200 = 800 bees.
Each bee in the first hive produces 500/1000 = 0.5 liters
The second hive has bees each producing 1.4*0.5 = 0.7 liters
The total amount of honey produces by the bees in the second hive is 0.7*800 = 560
The total honey produced is 500+560 = 1060 liters