📅 Published: August 2026 · ✍️ By: PSLE Hero Editorial Team
Fractions form the core foundation of Primary 5 and Primary 6 Mathematics. In Paper 2 structured questions, fraction concepts are combined with ratios, decimals, and percentages. Understanding the core fraction patterns and avoiding subtle exam traps can mean the difference between AL1 and AL3.
📖 Related Maths Revision Guides:
• PSLE Maths Revision Tips (General paper strategy & timing)
• PSLE Maths Heuristics Guide (5 core heuristic types)
• PSLE Maths Model Drawing Guide (Part-Whole & Comparison models)
Most marks lost in fraction problem sums are not caused by weak multiplication or addition skills, but by misinterpreting what the fraction is operating upon.
Trap 1: Confusing "Fraction of a Set" with "Fraction of a Remainder"
"John spent 1/3 of his money on a book and 1/4 of his money on a pen" is completely different from "John spent 1/3 of his money on a book and 1/4 of the remainder on a pen." Always check whether the second fraction refers to the original total or the leftover amount.
Trap 2: Fraction as a Portion vs Fraction with Units
"Mandy had 3/4 kg of flour. She used 1/2 kg" vs "Mandy had 3/4 kg of flour. She used 1/2 of it." In the first sentence, 1/2 kg is a direct physical mass to subtract (3/4 - 1/2 = 1/4 kg left). In the second, 1/2 is a ratio portion (1/2 of 3/4 kg = 3/8 kg used).
Trap 3: Adding or Subtracting Denominators directly
Students under exam stress occasionally write 1/3 + 1/4 = 2/7. Always convert fractions to a common denominator before adding or subtracting.
Trap 4: Forgetting to Express Answers in Simplest Form
Leaving a final answer as 4/8 instead of 1/2 will result in a 1-mark deduction for final accuracy in short-answer questions.
When a problem sum mentions spending or giving away a fraction of the remaining amount, the Branching (or Tree) Method is the most efficient non-model heuristic.
Step 1: Set up the initial branch.
Total = 5/5.
Spent on Bag = 2/5.
Remainder = 1 - 2/5 = 3/5.
Step 2: Branch out from the Remainder.
Lunch = 1/3 of Remainder = 1/3 × 3/5 = 1/5 of original total.
Money Left = Remainder - Lunch = 3/5 - 1/5 = 2/5 of original total.
Step 3: Solve for the total.
2 units (Left) = $72
1 unit = $72 ÷ 2 = $36
Total (5 units) = 5 × $36 = $180.
When a question states that a fraction of one group is equal to a fraction of another group, equate the numerators to find the ratio between the two totals.
Step 1: Write down the equal fractions.
1/3 Alex = 2/5 Ben.
Step 2: Equate the numerators (LCM of 1 and 2 is 2).
Convert 1/3 to 2/6.
2/6 Alex = 2/5 Ben.
Step 3: Interpret the units.
Alex has 6 total units.
Ben has 5 total units.
Step 4: Calculate the difference.
Difference = 6 units - 5 units = 1 unit.
1 unit = $30.
Alex's Savings (6 units) = 6 × $30 = $180.
Use this 4-step checklist when reviewing your child's fraction homework:
Reinforce fraction concepts and heuristic problem sums with targeted practice questions designed for Singapore primary students.
Try Free Practice QuestionsFraction of a set refers to taking a fraction of the original total amount. Fraction of a remainder means taking a fraction of whatever amount is left over after the first item or portion has been subtracted.
When a question states that 1/3 of Group A is equal to 2/5 of Group B, you equate the numerators to find the common numerator (e.g. 2/6 of A = 2/5 of B). This reveals that Group A has 6 total units while Group B has 5 total units.
Students often fail to distinguish between a fraction representing a portion (e.g. 1/4 of the ribbon) and a fraction representing a fixed measurement unit (e.g. 1/4 metre of ribbon).