conversations.from: human
conversations.value: The difference between the price of an orange and the price of a pear equals the price of a banana. If the total cost of an orange and a pear is $120 and a pear costs $90, calculate the total price of buying 200 bananas and twice as many oranges as bananas.
  Can you solve this problem?
conversations.from: assistant
conversations.value: If the total cost of an orange and a pear is $120, and a pear costs $90, an orange costs $120-$90 = $30
  Since the difference between the price of an orange and a pear is the price of a banana, a banana is sold at $90-$30 = $60
  To buy 200 bananas, you'll pay $60*200 = $12000
  When you twice as many oranges as bananas, you buy 2*200 = 400 oranges.
  The total cost of buying 400 oranges is 400*30 = $12000
  The total price of buying 200 bananas and twice as many oranges as bananas is $12000+$12000 = $24000