prompt: Mark hires a singer for 3 hours at $15 an hour.  He then tips the singer 20%.  How much did he pay?
messages.content: Mark hires a singer for 3 hours at $15 an hour.  He then tips the singer 20%.  How much did he pay?
messages.role: user
messages.content: The cost was 15*3=$<<15*3=45>>45
  So the tip was 45*.2=$<<45*.2=9>>9
  So in total, he paid 45+9=$<<45+9=54>>54
  #### 54
messages.role: assistant