1 roll can wrap 5 shirt boxes and he has 20 shirts boxes to wrap so he needs 20/5 = <<20/5=4>>4 rolls of wrap
1 roll can wrap 3 XL boxes and he has 12 XL boxes to wrap so he needs 12/3 = <<12/3=4>>4 rolls or wrap
All total he needs 4+4 = <<4+4=8>>8 rolls of wrap
Each roll costs $4.00 and he needs 8 rolls so it will cost him 4*8 = $<<4*8=32.00>>32.00 in wrapping paper
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