Show model answer and explanation
473
Add ones, tens and hundreds, regrouping as needed.
Class 3 · English Medium · Cambridge · Mathematics
Written addition and subtraction
Explore written addition and subtraction with an example and your own answers.
About this lesson and its coverage
Original Kidemy foundation practice · Read the example, write your answers, then check. This starter is shared across class versions; it is not a complete board-specific lesson or course.
Open this topic in Skills Lab →
Learn the idea
Line up equal place values. Regroup ten ones as one ten, or exchange a ten for ten ones when subtracting.
Worked example
248 + 135: 8 + 5 = 13 ones. Carry one ten; the total is 383.
- Read the example and explain which rule or evidence it uses.
- Try each task yourself, then compare the answer and its reason.
Your written practice
Show your working on paper. Check your answer, then choose Next.
Show model answer and explanation
324
Exchange across the zero before subtracting the ones.
Show model answer and explanation
135
Find the difference between 400 and 265.
Take it further
Apply the idea in a new situation and explain your method. Open writing needs a guardian or teacher to review it.
Show model answer and explanation
693
Regroup thirteen ones into one ten and three ones.
Show model answer and explanation
442
Exchange across the zeros before subtracting.
Write in your own words. A guardian or teacher should review this response.
Show model answer and explanation
The carried tens and hundreds were omitted. 15 ones give 1 ten and 5 ones; 6+5+1=12 tens; the total is 425.
Explain both exchanges and give 425.
Progress and browser storage
Notebook challenge, sources and further study
Teacher-led lessons, schedules and prices for this outline are upcoming. You can use any starter practice above now without booking.
Your next step
Solo practice works without an account. Sign in to save a practice record to your learner profile.
Keep practising
Exact lesson links and related activities are labelled separately. Return-to-course links retain your selected learning path.
Play this exact lesson in Skills Lab →
Related visual multiplication, division and fractions →
Related Stage 3 maths companion · confirm programme placement →