1990, the cost of tuition at a large Midwestern university was $101 per credit hour. In 2005, tuition had risen to $236 per credit hour.
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Solution:
According to the problem, the linear equation would be:
[tex]C(X)=101+9(x-1990)[/tex]now, if x=2013, the tuition will be:
[tex]C(2013)=101+9(2013-1990)=101+9(23)[/tex]this is equivalent to
[tex]C(2013)=101+9(23)=308[/tex]