conversations.from: human
conversations.value: Tom's cat needs an expensive surgery.  He has had pet insurance for 24 months that cost $20 per month.  The procedure cost $5000 but the insurance covers all but 20% of this.  How much money did he save by having insurance?
conversations.from: assistant
conversations.value: The insurance cost 24*20=$480
  With insurance he pays 5000*.2=$1000 for the procedure
  So he paid 1000+480=$1480
  So he saved 5000-1480=$3520