Let z be the number of zoology books and b be the number of botany books.

We know that z + b = 80 and b = 4z.

Substituting the second equation into the first equation, we get z + 4z = 80

Combining like terms, we get 5z = 80

Dividing both sides by 5, we get z = 16

# Answer

16
<|im_start|>system
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<|im_start|>user
Milton has some books about zoology and 4 times as many books about botany. If he has 80 books total, how many zoology books does he have?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
16
Milton has some books about zoology and 4 times as many books about botany. If he has 80 books total, how many zoology books does he have?
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