First subtract the 12 confiscated firecrackers from the original number: 48 firecrackers - 12 firecrackers = <<48-12=36>>36 firecrackers

Then multiply this number by 1/6 to find how many were defective: 36 firecrackers * 1/6 = <<36*1/6=6>>6 firecrackers

Then subtract the defective firecrackers to find how many were good: 36 firecrackers - 6 firecrackers = <<36-6=30>>30 firecrackers

Then divide this number in half to find how many firecrackers Jerry set off: 30 firecrackers / 2 = <<30/2=15>>15 firecrackers

# Answer

15
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Jerry bought 48 firecrackers for the 4th of July. A police officer discovered and confiscated 12 of them. 1/6 of the remaining ones were defective. If Jerry set off half the good firecrackers, how many firecrackers did he set off?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
15
Jerry bought 48 firecrackers for the 4th of July. A police officer discovered and confiscated 12 of them. 1/6 of the remaining ones were defective. If Jerry set off half the good firecrackers, how many firecrackers did he set off?
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