integer

Everyday

(maths) A whole number that can be positive, negative or zero, with no fraction or decimal part: … −3, −2, −1, 0, 1, 2, 3 … tree →

In the lessons

A key maths word: «give your answer as an integer», «list the integers between −2 and 3». Integers are used for temperatures below zero, floors below ground, and money owed. Phrases: «positive integer», «negative integer», «consecutive integers», «the nearest integer».

Examples

• 5, 0 and −7 are all integers. tree →
• 3.5 is not an integer. tree →
• Round 4.6 to the nearest integer: the answer is 5. tree →
• Find two consecutive integers that add up to 15: 7 and 8. tree →
• The temperature was −4, a negative integer. tree →
• List the integers between −2 and 2: −1, 0, 1. tree →

Note

Countable. Pronounced «IN-tuh-jer» (soft g). Not fractions or decimals. «Positive integers» start at 1; zero is neither positive nor negative. Consecutive integers differ by 1. «Whole number» in schools often means 0, 1, 2… (no negatives).