A number can be a factor of one quantity without being a factor of another. To find a common factor, a Primary 4 learner must check both relationships. For Potong Pasir parents considering Mathematics tuition, that word ‘common’ gives the task a specific demand.
Choose a weekday when your child can settle after school and travel with enough attention to organise factor pairs. Choose a weekend when a rested start supports that reasoning better. Leave room later for one independent check.
Before selecting a slot, inspect whether the child distinguishes factors from multiples and understands what the question asks to maximise. A short original attempt can make the teaching need clear.
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Find the starting point · Explore the worked example · Compare lesson days · Check the teaching · Review independence
Ask which numbers divide both quantities exactly
A factor divides a whole number without a remainder. A common factor must do that for both numbers under consideration.
Ask your child to explain why a proposed factor belongs to each number. Factor pairs can help organise the search rather than leave the learner guessing individual values.
If the multiplication facts are uncertain, they may interrupt the factor search. If the facts are secure but the relationship is confused, teach what factors describe.
The greatest common factor of eighteen and thirty
The positive factors of 18 are 1, 2, 3, 6, 9 and 18. The positive factors of 30 are 1, 2, 3, 5, 6, 10, 15 and 30.
The common factors are 1, 2, 3 and 6, and the greatest is 6. Nine divides eighteen exactly but not thirty, so it cannot be common. The largest factor of one number alone does not settle the question.
For a fresh check, find the greatest common factor of 16 and 24. Their common factors are 1, 2, 4 and 8, giving 8. Ask your child to justify membership in both lists.
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Protect attention for the two checks
A weekday lesson can fit well when there is a genuine settling period. A tired learner may find factors of the first number and forget to test the second.
A weekend may provide more patient organisation, but inspect the surrounding commitments. Another demanding activity immediately beforehand can remove the benefit of a rested start.
For Potong Pasir families, assess the complete journey to the confirmed teaching venue and home again. Confirm the available time and class fit before organising other activities around either option.
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Make the search complete and traceable
Useful teaching shows how factor pairs organise each list. The child should be able to explain why the search has included every positive factor needed for the comparison.
Then vary the pair of numbers and include a case with only one as a common factor. The learner should use the relationships rather than expect a convenient larger answer every time.
In a 3-pax group, ask how each child checks a fresh pair independently. A tutor should inspect both the generated factors and the selection of the greatest common value.
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Check the meaning after the model is removed
Later in the week, offer a different pair with manageable numbers. Leave the worked lists out of sight and allow your child to choose a valid method.
If the lists are wrong, target the factor relationships or arithmetic. If they are correct but the selected value belongs to only one, return to the meaning of common.
The preferred lesson day supports thoughtful participation and proportionate follow-ups. Organised pairs, meaningful checks and fewer prompts provide practical evidence when reviewing the teaching plan.
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Make the starting position clear
The Primary 4 Mathematics tuition overview provides the wider level route. Bring current school materials, a recent independent attempt and a note of the first step that needed help. Preserve the original working so the tutor can inspect your child’s own decisions.
The Potong Pasir tutor guide describes enquiries for families considering the Bukit Timah teaching location near Sixth Avenue MRT. Potong Pasir identifies the families addressed here; confirm the teaching venue and placement directly. The MOE primary curriculum and syllabus page provides the official curriculum route.
For a parent–student consultation, share your preferred weekdays or weekends, actual travel starting point and child’s usual energy pattern. Confirm the available lesson time, teaching venue and class fit before enrolment. Sign up after the starting position is clear and the weekly arrangement looks sustainable.