Answer:
The constant of proportionality is 47 dollars/week
![k=47\text{ dollars/week}](https://img.qammunity.org/2023/formulas/mathematics/college/86mfw22qbxa6hz0qkfwsv4lkbpvqxw6hvy.png)
Step-by-step explanation:
From the graph;
The total savings (t) is directly proportional to the number of weeks (n).
![\begin{gathered} t\propto n \\ t=kn \\ k=(t)/(n) \\ k=(\Delta t)/(\Delta n) \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/kj1p5pr4y81gymbcmtblkrovy4o153qku9.png)
Where k is the constant of proportionality.
From the graph;
Total Savings starts from 0 and ends on 470 dollars
while the number of weeks starts from 0 to 10 weeks.
![\begin{gathered} k=(\Delta t)/(\Delta n)=(470-0)/(10-0)\text{ dollars/week} \\ k=(470)/(10)\text{ dollars/week} \\ k=47\text{ dollars/week} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/qz3sxoedkb99tuclneqkduhn8hmnang4ss.png)
Therefore, the constant of proportionality is 47 dollars/week