conversations.from: human
conversations.value: Please show me the solution for: Melisa and Jennifer threw a fiftieth birthday party for their father at a local restaurant. When the bill came, Melisa added a 15% tip of $42. Jennifer said that the service was wonderful and they should leave a 20% tip instead. How much is a 20% tip?
conversations.from: assistant
conversations.value: If 15% is known to be $42, then 5% can be found by dividing $42 ÷ 3 = $14.
  So 20% is $14 + $42 = $56.