We first calculate the proportion of all the other apples: 1/6 + 1/4 + 1/12 = 2/12 + 3/12 + 1/12 =6/12

So, the proportion of perfect apples is 12/12 - 6/12 = 6/12 = 0.5.

Thus the number of perfect apples is 0.5 * 30 = <<0.5*30=15>>15

# Answer

15
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
In a batch of 30 apples, 1/6 are too small and 1/3 are not ripe.  The others are perfect. Calculate the number of perfect apples.
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
15
In a batch of 30 apples, 1/6 are too small and 1/3 are not ripe.  The others are perfect. Calculate the number of perfect apples.
train