question: Theo bought a pen for $2 and a piece of paper that cost $1 less than three times the price of the pen. She gave the cashier $10. What is the amount of change Theo received?
answer: Three times the cost of pen is $2 x 3 = $<<2*3=6>>6.
  The cost of paper is $6 - $1 = $<<6-1=5>>5.
  The total cost for the pen and paper is $2 + $5 = $<<2+5=7>>7.
  Theo received $10 - $7 = $<<10-7=3>>3 change.
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