ANSWER
![(623)/(d)\text{ km per day}](https://img.qammunity.org/2023/formulas/mathematics/college/k5qiqy0j63h1j4kx3arc12px5j70fqbwsm.png)
Step-by-step explanation
Ethan rollerbladed a total of 623 km over d days and he rollerbladed the same distance each day.
We want to find how many kilometres he rollerbladed each day, in other words, the rate at which he rollerbladed.
To do that, we have to divide the total distance he rollerbladed by the number of days he spent.
That is:
![(623)/(d)\text{ km per day}](https://img.qammunity.org/2023/formulas/mathematics/college/k5qiqy0j63h1j4kx3arc12px5j70fqbwsm.png)
That is the answer.