conversations.from: human
conversations.value: John gets his pool cleaned every 3 days.  It cost $150 each time and he gives the guy a 10% tip each time he comes to clean.  Then twice a month he needs to use $200 of chemicals.  How much does his pool cost a month?
conversations.from: assistant
conversations.value: He gets his pool cleaned 30/3=10 times a month
  Each time he gets it cleaned he tips 150*.1=$15
  So he pays 150+15=$165
  So he pays 165*10=$1650 a month on cleaning
  The chemicals cost 200*2=$400
  So in total, he pays 1650+400=$2050