conversations.from: human
conversations.value: Colston knows that his teacher loves drinking coffee and one day wants to see how much she drinks each week. He sees that she has a 20-ounce thermos and when she makes her coffee she pours a 1/2 cup of milk in, and then fills the coffee to the top. She does this twice a day. After the five-day school week, he decides to tell her, and when she hears how much coffee she drinks, she decides to drink 1/4 of what she normally drinks. How many ounces of coffee does she now drink a week?
conversations.from: assistant
conversations.value: 1/2 a cup = 4 ounces
  Each thermos contains 16 ounces of coffee because 20 - 4 = 16
  She drinks 32 ounces a day because 2 x 16 = 32
  She drinks 160 ounces a week because 32 x 5 = 160
  She starts drinking only 40 ounces because 160 / 4 = 40