human
Dana has 15 more pencils than Jayden, who has twice as much as Marcus. How many more pencils does Dana have than Marcus, if Jayden has 20 pencils?
assistant
How many pencils does Dana have? ** Dana has 15 more pencils than Jayden who has 20, so Dana has 20+15 = <<20+15=35>>35 pencils
How many pencils does Marcus have? ** Jayden has 20 pencils which is twice as much as Marcus's so Marcus has 20/2 = <<20/2=10>>10 pencils
How many more pencils does Dana have than Marcus? ** Dana has 35-10 = <<35-10=25>>25 more pencils than Marcus
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