Integers

• Integers are …, −3, −2, −1, 0, 1, 2, 3, … The place of a digit sets its value.
• Directed numbers describe real situations such as temperatures, heights above and below sea level, and bank balances.
• To order integers, picture a number line: the further left, the smaller (−12 < −7).
• Use the four rules accurately, including with negative numbers, and follow the order of operations (brackets, indices, ÷ and ×, + and −).
• Know the words odd, even, prime, factor and multiple, and write a number as a product of its prime factors.

What a digit is worth

An integer is a whole number. It can be positive, negative or zero. The place value of a digit is the column it sits in: units, tens, hundreds, thousands, ten thousands and so on. In 4 672 015 the 7 is in the ten-thousands column, so it is worth 70 000.

To order integers, place them on a number line. A negative number with a bigger size is smaller: −12 is further left than −7, so −12 < −7.

Temperatures, sea level and money

Directed numbers have a sign that shows direction: above or below zero, gain or loss, credit or debt. A rise means add; a fall means subtract. The difference between two values is the larger minus the smaller, and it is always positive.

Brackets, then indices, then ÷ and ×, then + and −

Use the four rules (add, subtract, multiply, divide) with whole numbers by a written method and check with a calculator. When a calculation mixes operations, work in this order:

The vocabulary of whole numbers

Even odd