How many liters are equivalent to one cubic decimeter?

One cubic decimeter is exactly equivalent to one liter because both measurements are defined based on the metric system. To understand this equivalence, it's important to recall that a cubic decimeter refers to a cube that has sides measuring one decimeter (dm) long.

Since one decimeter is equal to 10 centimeters, a cubic decimeter can also be expressed in cubic centimeters. Hence, one cubic decimeter is equal to (10 , \text{cm} \times 10 , \text{cm} \times 10 , \text{cm} = 1000 , \text{cm}^3). In the metric system, one liter is defined as the volume of one cubic decimeter, which reinforces that one cubic decimeter equals one liter.

This relationship is fundamental in the metric system, making it a useful conversion when dealing with volume measurements. Therefore, the correct answer indicates the direct and established equivalence of these two units.