Number

Upper bound

The largest value a rounded measurement could be. For a length given as 12 cm to the nearest cm, the upper bound is 12.5 cm.

Definition

When a measurement is rounded, the upper bound is found by adding half the rounding unit. For 12 cm (nearest cm), upper bound = 12 + 0.5 = 12.5 cm. The upper bound itself is excluded — it is the supremum.

Used in these topics

Bounds and error intervals →

Related terms

Lower bound

The smallest value a rounded measurement could be. For 12 cm to the nearest cm, the lower bound is 11.5 cm.

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