Two quantities that have the same measure or correspond to each other are said to be what?

• A. Equal
• B. Equivalent to
• C. Identical
• D. Similar

Answer: (B)

Equivalence is about sameness within a context. If two quantities represent the same amount or match up under a given rule or unit, we say they are equivalent to each other. This captures the idea that they can stand in for one another in calculations, even if they’re written in different forms. For example, 1 kilometre is equivalent to 1000 metres, and the fractions 1/3 and 2/6 are equivalent because they express the same portion.

It’s not about being literally identical in all respects, or about shape or form. That’s why the other terms don’t fit as well: equal is a stricter idea of exact sameness in value (often after converting to a common unit), identical means the exact same object or instance, and similar refers to resemblance in form rather than exact quantity.