60% of female alligators are adults because 100 - 40 = <<100-40=60>>60
There are 25 female alligators because 15 / .6 = <<15/.6=25>>25
There are 50 alligators in total because 25 / .5 = <<25/.5=50>>50
There are 25 male alligators because 50 / 2 = <<50/2=25>>25
#### 25