conversations.from: human
conversations.value: I need help with this problem:
  Preston has a sandwich shop. He charges $5 for each sandwich. He also charges $20 for a delivery fee. Abra Company orders 18 sandwiches from Preston and also tips him 10%. How much total, in dollars, did Preston receive?
conversations.from: assistant
conversations.value: First, find the price of the sandwiches $5 per sandwich * 18 sandwiches = $90.
  Now add in the delivery fee $90 + $20 = $110.
  Now the tip $110 * 0.10 = $11.
  Add the tip to the price of the sandwiches $110 + $11 = $121 in total.