Ethan rollerbladed a total of 623 km over $d$ days. He rollerbladed the same distance each day. We need to find how many kilometers Ethan rollerbladed each day, and express the answer as an expression.

1. Problem Description

Ethan rollerbladed a total of 623 km over $d$ days. He rollerbladed the same distance each day. We need to find how many kilometers Ethan rollerbladed each day, and express the answer as an expression.

2. Solution Steps

The total distance is 623 km, and the number of days is $d$. Since the distance is the same each day, we can find the distance per day by dividing the total distance by the number of days.

Distance per day = $\frac{\text{Total distance}}{\text{Number of days}}$

In this case,

Distance per day = $\frac{623}{d}$

3. Final Answer

$\frac{623}{d}$