11+ Maths: Multiply & Divide by Powers of Ten
21 October 2026
Understanding powers of ten
Multiplying and dividing by powers of ten is a key skill for the 11+ maths exam. It helps children work quickly with large and small numbers, decimals and place value.
Multiplying by a power of ten
When you multiply a number by 10, 100 or 1000, each digit moves to the left. The number of places moved matches the number of zeros in the power of ten.
Worked example: multiplying by 100
5.4 × 100
First, count the zeros in 100. There are 2 zeros, so move each digit 2 places to the left.
5.4 becomes 540.
The answer is 540.
Dividing by a power of ten
When you divide by 10, 100 or 1000, each digit moves to the right. Again, the number of places moved matches the number of zeros in the power of ten.
Worked example: dividing by 1000
720 ÷ 1000
Count the zeros in 1000. There are 3 zeros, so move each digit 3 places to the right.
720 becomes 0.72.
The answer is 0.72.
Key points to remember
Multiplying by powers of ten moves digits left. Dividing moves digits right. The number of places depends on the number of zeros in the power of ten.
Key insight: Use place value charts
Encourage your child to use a place value chart when practising. Writing the number in the chart and shifting the digits helps make the process clear and reduces mistakes.
