Primary 6 Mathematics tuition in Bayshore can help a pupil identify which quantity a percentage uses as its whole. In a profit question, the profit amount and the selling price are not interchangeable. A correct subtraction still needs the correct reference amount for the percentage.
For parents comparing weekday or weekend lessons, the useful question is when the child can explain that reference amount calmly. One pupil may benefit from a timely weekday correction; another may need a weekend discussion with a labelled model.
eduKate’s diagnosis-first approach starts with the child’s actual working. Focused 3-pax support should make the cost, selling price and profit visible. The chosen rhythm should fit school learning and the pupil’s available energy.
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Identify the learning need · Consider weekdays · Consider weekends · Try the worked example · Review your next step
Article contents
Ask the child to distinguish cost price from selling price. Their difference gives the profit amount when there are no other costs.
If the question asks for profit as a percentage of cost price, the denominator is the cost price. State that basis rather than relying on an unexplained rule.
Profit as a percentage of selling price is a different proportion. The numerator may stay the same while the reference whole changes.
A weekday lesson can revisit a recent percentage question and locate the point where the denominator changed. Bring the original attempt, not just the final answer.
Allow a pause after school before careful explanation. The pupil should be able to say why the chosen quantity represents 100%.
Use one short variation with a new pair of prices. This tests whether the pupil selects the basis from the question rather than remembers one percentage.
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A weekend can provide room to calculate the same profit relative to cost and relative to selling price. The contrast shows why the denominator matters.
Use fictional prices so the lesson stays focused on mathematics. There is no need to introduce claims about actual products or businesses.
Arrange a brief weekday revisit. Independent identification of the reference amount is the useful check.
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A fictional item costs $80 and is sold for $100. There are no additional costs. Find the profit as a percentage of the cost price.
The profit is $100 − $80 = $20. This is the amount gained, not yet a percentage.
Use the stated reference whole: profit ÷ cost × 100% = 20/80 × 100% = 25%.
Check: 25% of $80 is $20, and adding that profit to the cost gives $100.
The calculation 20/100 × 100% = 20% describes profit as a percentage of selling price. It is a valid different proportion, but does not answer the stated question.
Try a fresh version: an item costs $60 and sells for $75. Its profit is $15, which is 15/60 × 100% = 25% of cost.
This model excludes extra expenses. If transport, fees or another cost are supplied, read how the question defines the total cost before calculating profit.
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A tutor should ask each pupil what the denominator represents. That question distinguishes a reference-whole misunderstanding from an arithmetic slip.
Comparing fraction and percentage-unit methods can show how both express the same proportion. The pupil should understand the connection rather than copy a preferred-looking sequence.
End with an independent problem and a reverse check. The calculated percentage should reproduce the profit when applied to the stated reference amount.
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Confirm current school scope, the actual venue and available lesson times before comparing concentration, journey and other responsibilities.
Set a narrow review target: identify profit, select the stated whole and verify the resulting percentage.
Look for successful explanation when the question changes its reference amount. A remembered 25% is not enough to show that distinction.
Weekday and weekend support are both possibilities. Select the routine that makes careful reasoning and short revisits practical.
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References and next steps
Official examination reference: SEAB PSLE formats examined in 2026, including separate Standard and Foundation Mathematics specifications. Use the document for the pupil’s examination year and level, and the school’s current assessment instructions. Worked examples are original teaching illustrations; suggested routines are practical options rather than official assessment requirements.
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