Answer:
The constant of proportionality for the group of boxes is: 25
Explanation:
Proportion means that change in one quantity causes change in other quantity. Direct variation means that increase in one quantity causes increase in the other quantity.
Let l be the length and v be the volume
Then according to given statement
V∝l
Removing the proportionality symbol introduces a constant in the equation
![V = kl](https://img.qammunity.org/2021/formulas/mathematics/high-school/rjcscvpaf6zceci6l4h93uk5usj5dm1yz3.png)
Putting V = 325 and l = 13
![325 =k(13)\\k = (325)/(13)\\k = 25](https://img.qammunity.org/2021/formulas/mathematics/high-school/4ttur2d4gdiv9ik5snb70tck2ikwcyq21k.png)
Hence,
The constant of proportionality for the group of boxes is: 25