The median family income is the "middle income: - half the families have this income or more, and half have a lesser income. The median family income can be approximated by: f(x) = 18,724.85 + 13,530.74 ln x (x is greater than or equal to 5) where x=5 corresponds to the year 1995.

a) What was the median family income in 2009? What is it this year?

b) If this model remains accurate, when will the median family income reach $62,500?

Question

The median family income is the "middle income: - half the families have this income or more, and half have a lesser income. The median family income can be approximated by: f(x) = 18,724.85 + 13,530.74 ln x   (x is greater than or equal to 5) where x=5 corresponds to the year 1995.

a) What was the median family income in 2009? What is it this year?

b) If this model remains accurate, when will the median family income reach $62,500?

mathteacher1729 · Answer

Do you see a pattern here...

  x =__ means 2004? 
  x = 5 means 2005
  x = __ means 2006?
  x = __ means 2007?
  x = __ means 2008?
  x = __ means 2009?

mathteacher1729 · Answer

@kmsully28 was my answer helpful? (I guess not...) 
What is giving you difficulty with this problem? 

Graphing makes it very very easy to solve. But you can solve it algebraically without much more difficulty too.