He needed 2 boxes of candles, because 5 / 2.5 = <<5/2.5=2>>2

He needed 24 candles because 2 x 12 = <<2*12=24>>24

He is 8 because 24 / 3 = <<24/3=8>>8

# Answer

8
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Kerry is ready to celebrate his birthday and wants to have three cakes with his age in candles on each of them. Candles come in boxes of 12 and cost $2.5 a box. If the candles cost $5, how old is Kerry?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
8
Kerry is ready to celebrate his birthday and wants to have three cakes with his age in candles on each of them. Candles come in boxes of 12 and cost $2.5 a box. If the candles cost $5, how old is Kerry?
train