<human>:  A local park has 70 pigeons that call the park home. Half of the pigeons are black, and 20 percent of the black pigeons are male. How many more black female pigeons are there than black male pigeons?
<bot>: How many pigeons are black? ** Black:70/2=<<70/2=35>>35 pigeons
How many pigeons are black males? ** Black Male: 35(.20)=7 pigeons
How many female black pigeons are there? ** 35-7=<<35-7=28>>28 female black pigeon
How many more black female pigeons are there than black male pigeons? ** There are 28-7=<<28-7=21>>21 more black female pigeons
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