Advanced Placement (AP) Computer Science

Disable ads (and more) with a membership for a one time $2.99 payment

Prepare for the AP Computer Science Exam. Study with flashcards and multiple choice questions, each question has hints and explanations. Get ready for your exam!

Each practice test/flash card set has 50 randomly selected questions from a bank of over 500. You'll get a new set of questions each time!

Practice this question and more.

Which of the following best defines the term "round-off" error?

An error due to exceeding memory limits.
An error that occurs when data is lost permanently.
An error when not enough bits represent the actual number.
An error caused by incorrect algorithm selection.

The correct answer is: An error when not enough bits represent the actual number.

Round-off error refers to the inaccuracies that arise when a number cannot be precisely represented in a digital system due to limitations in the number of bits available to store it. This situation typically occurs in floating-point arithmetic, where some numbers must be approximated because the binary representation cannot precisely capture their decimal values. For instance, if a number like 0.1 cannot be precisely represented in a binary format, the nearest representation may be used, leading to a small error in calculations. This is particularly significant in numerical computations, where cumulative rounding errors can impact the final results. Hence, the definition recognizing that round-off error occurs due to insufficient bits to represent a number accurately captures the essence of this type of error accurately.