Carrying and borrowing
Adding and subtracting with carrying is where many get stuck: you have to watch each column and not forget the one you carry. Here it is practised with column sums and a help that goes step by step.
What you practise
- The column sum, with each digit under its partner.
- Additions with carrying and subtractions with borrowing, from fewer to more digits.
- A help that explains a single idea at each step, with an example similar to the exercise.
- The most common slips — forgetting the one you carry, taking the small digit from the big one — are noted for the adult.
How it adapts
The technique in the help changes with the level: counting, making ten, splitting into tens and units. The starting level comes from age and how much help is needed.
Frequently asked questions
- What does “carrying” mean?
- That when a column adds up to more than nine, you carry one to the next; when subtracting, that you borrow.
- Can you see what is going wrong?
- Yes, but only the adult can: the most common slips (forgetting the carry, subtracting the wrong way round) are noted in the progress screen.
- Can I try it for free?
- Yes, with no account: every day there are free exercises for each skill.
Guides to practise
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