conversations.from: human
conversations.value: At a CD store, 40% of the CDs cost $10 each, and the rest cost $5 each. Prince bought half the CDs sold at $10 each, and all of the CDs sold at $5 each. If the total number of CDs was 200, how much money did Prince spend on buying the CDs?
  What is the solution?
conversations.from: assistant
conversations.value: The number of CDs selling at $10 each at the store is 40/100*200 = 80
  This means the store sells 200-80 = 120 CDs at $5 each.
  Prince bought 1/2*80 = 40 of the CDs selling at $10 each.
  The total amount of money Prince paid for the 40 CDs selling at $10 each is $40*10 = $400
  If he bought all the CDs selling at $5 each, he paid a total of $5*120 = $600
  For all the CDs he bought, Prince spent $600+$400= $1000