Number Bonds Practice
Practise number bonds — the pairs that add up to 10, 20 or 100. Knowing these by heart makes mental math fast.
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What number bonds are
A number bond is a pair of numbers that add up to a target — most importantly 10. Knowing instantly that 7 needs 3 to make 10 is one of the highest-value facts in early math: it powers the “make ten” strategy for addition and subtraction.
- Look at the number you have and the target.
- Ask: how much more do I need to reach the target?
- That missing amount is the bond — 6 and 4 are a bond for 10.
Worked examples
Tips & common mistakes
The bonds to 10 are worth memorising cold — 0&10, 1&9, 2&8, 3&7, 4&6, 5&5. Once those are automatic, bonds to 20 and to 100 follow the same idea. Tap the missing number.
- Counting up slowly each time instead of just knowing the pair.
- Overshooting the target (saying 7 + 4 = 10).
- Forgetting 0 and the target itself form a bond (0 + 10 = 10).
Frequently asked questions
What is a number bond?
A pair of numbers that add to a target. For 10, the bonds are 0&10, 1&9, 2&8, 3&7, 4&6 and 5&5.
Why are bonds to 10 so important?
They power the ‘make ten’ strategy, which makes adding and subtracting within 20 fast and reliable.
What grade are number bonds?
They’re a kindergarten through grade 2 skill, and the bonds to 10 are worth memorising early.
What are bonds to 100?
Pairs of tens that make 100 — like 30 and 70, or 60 and 40. Same idea, bigger target.
How do I practise these at home?
Quick-fire questions — ‘what goes with 8 to make 10?’ — a minute a day builds instant recall.