Human: Bruno wants to buy two and one-half dozens of pens. How many pens will he have? Assistant: 
How many dozens are there? ** Since a dozen is equal to 12, then two dozens are equal to 12 x 2= <<24=24>>24.
How many half-dozens are there? ** One-half dozen is equal to 12/2 = <<12/2=6>>6.
How many pens will he have? ** Thus, Bruno will have a total of 24 + 6 = <<24+6=30>>30 pens.
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