The total ratio of cattle on the farm is 10+27 = <<10+27=37>>37

Since the fraction that represents bulls from the total ratio is 27/37, the number of bulls on the farm is 27/37*555 = <<27/37*555=405>>405

# Answer

405
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
The ratio of cows to bulls in a barn is 10:27. If there are 555 cattle on the farm, how many bulls are on the farm?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
405
The ratio of cows to bulls in a barn is 10:27. If there are 555 cattle on the farm, how many bulls are on the farm?
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