The company has been able to determine that its sales in dollars depend on advertising and of the number of sellers and for this reason, it uses the data from previous years to be able to forecast possible sales for the year 2010.

Y X1 ($ 000) X2 ($ 000)

Year Sales Advertising Salesman

2003 $ 10 $ 1 1

2004 $ 15 $ 2 1

2005 $ 25 $ 3 2

2006 $ 40 $ 5 3

2007 $ 70 $6 3

2008 $ 110 $ 8 4

2009 $ 150 $ 9 6

INSTRUCTIONS:

a) Calculate the values of the letters a, b1, b2.

b) Write down the problem Regression equation

c) Calculate sales by 2010 if the advertising were $ 14,000 and the number of sellers out of 10.