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AP®︎/College Computer Science Principles

Course: AP®︎/College Computer Science Principles > Unit 1

Lesson 3: Limitations of storing numbers

Number limits, overflow, and roundoff

AP.CSP: DAT‑1 (EU), DAT‑1.B (LO), DAT‑1.B.1 (EK), DAT‑1.B.2 (EK), DAT‑1.B.3 (EK)

A scientist is running a program to calculate the volume of a cone:

radius ← 17.24
height ← 5.24
volume ← PI * (radius * radius) * (height / 3)

The code relies on the built-in constant PI. After running the code, the variable volume stores 1630.9266447568566.

Their supervisor checks their results by running the same calculation on their own computer. Their program results in a volume of 1630.9266447564448.

The two values are very close, but not quite the same.

Which of these is the most likely explanation for the difference?

(Choice A)
One of the computers has a bug in its mathematical operations.
(Choice B)
The two computers executed the arithmetic operations using a different order of operations.
(Choice C)
One computer used an integer representation for the numbers while the other computer used the more accurate floating-point representation.
(Choice D)
The two computers represent the constant PI with a different level of precision, due to their rounding strategy or size limitations.
(Choice E)
One of the computers experienced an integer overflow error when calculating the result.

🤔

[What language is the code in?]

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AP®︎/College Computer Science Principles

Course: AP®︎/College Computer Science Principles > Unit 1

Problem