Given :
The cost of 5 pounds of boudin is $26.
To Find :
The constant of proportionality that relates the cost in dollars y, to the number of pounds of boudin x .
Solution :
Price per boudin in terms of x and y is :
[tex]P=\dfrac{y}{x}[/tex]
Price per boudin by given data :
[tex]P=\dfrac{26}{5}[/tex]
So,
[tex]\dfrac{y}{x}=\dfrac{26}{5}\\\\y = \dfrac{26}{5}x[/tex]
Therefore, the constant of proportionality is [tex]\dfrac{26}{5}[/tex].
Hence, this is the required solution.