The following is an excerpt from a may 1, 2006, press release issued by the bureau of economic analysis. [monthly] disposable personal income (dpi) increased $78.4 billion . . in march [2006]† use function notation to represent the disposable personal income, m, at the end of march 2006 as a function of disposable personal income, f, at the end of february 2006. (both m and f are in billions of dollars.) m(f) =

M(F) = F + 78.4

Step-by-step explanation:

* Lets explain how to solve the problem

- The monthly disposable personal income (DPI) increased

  $78.4 billion in March 2006

- M is the disposable personal income at the end of March 2006

- M is a function of disposable personal income, F, at the end of

 February 2006

∴ The function is M(F), where M(F) is the disposable personal income

   at the end of March 2006 and F is the disposable personal income

   at the end of February 2006

∵ The monthly disposable personal income (DPI) increased

   $78.4 billion in March 2006

- That means the disposable personal income (DPI) in March is the

  sum of the disposable personal income (DPI) in February and

  $78.4 billion

∵ M and F both are in billions dollars

∵ M(F) in billions dollars

∴ M(F) = F + 78.4

# Remember :  we don't have to put 78.4 × 10^9 because the three

  terms of the function are in billion

were is the equation