lesson
Two partial products have different values
1 · Learn
Multiplying by a two-digit number can be split into tens and ones. In 1,326 × 24, the 2 means 20, so its partial product must be twenty times 1,326. A misplaced tens row makes the answer ten times too small for that part.
Align columns when adding the partial products. Estimate before calculating and check using the distributive relationship afterwards.
2 · Worked example
1,326 × 4 = 5,304 and 1,326 × 20 = 26,520. Their sum is 31,824. Both parts represent the full multiplier 24.
3 · Your turn
Calculate 2,143 × 32 using two partial products.
Check your answer
4,286 + 64,290 = 68,576.
4 · Apply your learning
Draw an area model labelled 30 and 2 to explain why the tens partial product is shifted.
Adult guidance and safety
Ask the learner to explain the method and check it using a different representation. Supply place-value grids, fraction strips, accurate diagrams and measuring tools where needed. These examples need varied practice; a short correct answer alone does not establish fluency.
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Check a calculation · Year 5 onward
Use this only when your teacher or adult allows a calculator for the task. Show your thinking first. It does not replace mental or written arithmetic and does not mark your lesson answer.
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