How to play Number Chain
Start with a number, follow each step in order, and keep the running total in your head. Also known as Mental maths chain, Running total, Maths warm-up.
The rules
- Start with the number at the beginning of the chain.
- Do each step to the running total, in order.
- Write the total after each step — or only the final answer in the challenge mode.
- Every step in a generated chain gives a whole number.
Playing Number Chain on Puzzle Solvers
- Choose every step or final answer only, how many steps, and a level, then press New Puzzle.
- Work out each step in your head and type the running total in the box (use the pad or keyboard; ↵ moves on).
- Boxes turn green when right. In ‘final answer only’ you keep it all in your head!
- Hint fills the next box and shows a quick way to work it out.
Using the Number Chain solver
- Type the chain — steps can be +7, −12, ×3, ÷4, double, half, square, root, cube, 25% (of), +10% (increase) or 3/4 (of).
- Press Solve to see every running total with a quick mental-maths method for each step.
A worked example
Start with 18. ×3 gives 54. Take away 6: 48. Double it: 96.
3/4 of 96: a quarter is 24, three quarters is 72. 25% of 72 is a quarter: 18 — back where we started!
Strategies
- Split and add. To multiply 36 × 4, do 30 × 4 = 120 and 6 × 4 = 24, then add: 144.
- Round and adjust. To add 39, add 40 and take away 1.
- Percentages. 50% is half, 25% is half of a half, 10% is divide by 10, 75% is three quarters.
- Fractions of. To find 3/4 of a number, divide by 4 and multiply by 3.
- Check with the inverse. After dividing, multiply back to check: 84 ÷ 7 = 12 because 12 × 7 = 84.
Common mistakes
- Applying a step to the original number instead of the running total.
- Mixing up ‘increase by 10%’ (×1.1) with ‘find 10%’ (÷10).
- Losing your place — say the running total to yourself after each step.
Where it comes from
Chains of mental arithmetic have long been a staple of classroom warm-ups and newspaper brain-training corners.
Frequently asked questions
Which level should children start with?
Easy suits ages 6–8 with tables up to 5 × 5; Medium suits ages 9–11.
Can I set my own chain?
Yes — the Number Chain Solver takes any chain you type and shows the working.
Is it good for a class?
Yes — put the daily chain on the board, or send it to Slate and work it together.
Are negative numbers used?
Generated chains stay positive; the solver accepts any whole-number chain.
Keep going
- Play Number Chaina fresh puzzle every time
- Number Chain Solverstep by step, every move explained
- BODMAS GameBuild equations that hit the target by applying the order of operations…
- Magic PathFind every number that fits the rule and join them all in one continuous path.
- Maths CrosswordA crossword where every clue is a maths question and the answers are numbers.
All guides: How to play every puzzle and game.