conversations.from: human
conversations.value: This math problem has got me stumped: Tina has 12 pink pens. She has 9 fewer green pens than pink pens. Tina has 3 more blue pens than green pens. How many pens does Tina have in total?
  Can you show me the way?
conversations.from: assistant
conversations.value: Tina has 12 - 9 = 3 green pens.
  Tina has 3 + 3 = 6 blue pens.
  In total Tina has 12 + 3 + 6 = 21 pens