conversations.from: human
conversations.value: Tom and Devin have been teaching for a total of 70 years. Devin has been teaching for 5 less than half the number of years that Tom has. How many years has Tom been teaching?
  Work out the solution step by step.
conversations.from: assistant
conversations.value: Let x be the number of years Tom has been teaching
  Devin has been teaching for (1/2)x-5 years
  70=x+((1/2)x-5)
  70=(3/2)x-5
  75=(3/2)x
  x=50
  Tom has been teaching for 50 years