There were 10*20 = <<10*20=200>>200 more bee-eaters at the zoo.
There were 1/2*100 = <<1/2*100=50>>50 cheetahs.
The total number of foxes and leopards is 80+20 = <<80+20=100>>100.
There were 2*100 = <<2*100=200>>200 alligators.
The total number of animals is 200 alligators+220 bee-eaters+100 snakes+80 tactic foxes+20 leopards+50 cheetahs = <<200+220+100+80+20+50=670>>670 animals.
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