11+ Maths: Multiply & Divide by Powers of Ten
26 October 2026
Multiply and divide by powers of ten practice
Multiplying and dividing by powers of ten is a key skill for the 11+ maths exam. It helps children work quickly and accurately with large and small numbers.
Understanding powers of ten
A power of ten is any number like 10, 100, 1000, and so on. Each time you multiply by ten, the digits move one place to the left. Each time you divide by ten, the digits move one place to the right.
Multiplying by powers of ten
When you multiply a number by 10, 100 or 1000, move every digit to the left for each zero. For example, multiplying by 100 means moving digits two places to the left. Any empty places are filled with zeros.
Dividing by powers of ten
When you divide by 10, 100 or 1000, move every digit to the right for each zero. Dividing by 100 means moving digits two places to the right. If there are not enough digits, add zeros after the decimal point.
Key insight: Moving the digits, not just the decimal point, helps children understand what happens to the value of the number when multiplying or dividing by powers of ten.
Worked example
Multiply 36.5 by 100
Step 1: Count the zeros in 100. There are two zeros, so move every digit two places to the left.
Step 2: 36.5 becomes 3650.
The correct answer is 3650.
Worked example
Divide 480 by 10
Step 1: There is one zero in 10, so move every digit one place to the right.
Step 2: 480 becomes 48.0.
The correct answer is 48.
Practice tip
Encourage your child to write out the digits and show the movement for each step. This helps make the change clear and avoids small mistakes.
Supporting your child
Regular practice with multiplying and dividing by powers of ten will build confidence. Use real-life examples, like money or measurements, to make the skill more meaningful.
