conversations.from: human
conversations.value: Mark got a 5% raise at his job.  Before the raise, he earned 40 dollars per hour.  He works 8 hours per day for 5 days per week.  His old bills used to be 600 dollars a week but he decided to add a hundred dollar a week personal trainer.  How much does he have leftover a week?
  Give me a solution to this problem
conversations.from: assistant
conversations.value: After the raise he earns 40*1.05=42 dollars an hour
  He works 8 hours per day so earns 42*8=336 per day
  He works 5 days per week so he earns 336*5=1680 a week
  His expenses after adding the personal trainer are 600+100=700 a week
  So he has 1680-700=980 left over