Constant of proportionality is given by: y=kx oy [tex]k=\frac{y}{x}[/tex]
So lets suppose y = 50 and x = 5 so k will be [tex]\frac{50}{5}=10[/tex]
This 10 will remain constant. For every $50 Michael saves $5, for $100 he will save $10 , for $150 he will save $15 and so on.
So this 'k' will be same for each value of x and y.
