KS2 SATs Maths: Place Value Revision Guide

What place value means

Every digit in a number has a value depending on its position. In 4,527, the 4 is worth 4,000 (thousands), the 5 is worth 500 (hundreds), the 2 is worth 20 (tens) and the 7 is worth 7 (ones).

Reading and writing large numbers

By Year 6 you need to read, write, order and compare numbers up to 10,000,000. Break big numbers into groups of three digits from the right (using commas) to make them easier to read, e.g. 6,304,215 is six million, three hundred and four thousand, two hundred and fifteen.

Rounding

To round a number, look at the digit to the right of the place value you're rounding to. If it's 5 or more, round up; if it's less than 5, round down. For example, 4,527 rounded to the nearest hundred is 4,500.

Negative numbers

Negative numbers are used in contexts like temperature. When ordering numbers that include negatives, remember -8 is smaller than -2, even though 8 is bigger than 2.

Common mistakes

• Misreading the number of zeros in very large numbers — count place value columns carefully.
• Rounding using the wrong digit — always check the digit immediately to the right of the place value you want.
• Forgetting that numbers become smaller, not bigger, as they go further below zero.