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PSLE Math Fractions & Decimals: Do's & Don'ts
11 Oct 2025·5 min read·The Tutor's Table
Weak fraction / decimal handling quietly drains marks across word sums, measurement, geometry, and graphs. Strong handling feels like a small superpower — you solve questions faster and with fewer slips.
Do's
- DO memorise common fraction ↔ decimal ↔ percentage conversions: 1/4 = 0.25 = 25%, 1/5 = 0.2, 1/8 = 0.125, 3/8 = 0.375, 2/3 ≈ 0.667.
- DO find a common denominator before adding or subtracting mixed numbers — always.
- DO simplify fractions at every step so the numbers stay small and friendly.
- DO convert decimals to fractions (or vice versa) whichever makes the calculation shorter.
- DO line up decimal points carefully when writing long multiplication / division by hand.
- DO estimate before solving: '1/3 of 450' should be around 150 — if you get 45 or 1350, stop and recheck.
Don'ts
- DON'T multiply or divide mixed numbers directly — convert to improper fractions first.
- DON'T 'cancel' diagonally without writing working. It causes silly errors under pressure.
- DON'T drop trailing zeros on money or measurement answers — $3.5 is wrong, $3.50 is correct.
- DON'T confuse '1/2 more' with '1/2 of'. Re-read the question when unsure.
- DON'T forget to convert the final fraction back to a mixed number if the question asks for one.
- DON'T write '0.50 = 1/2 = 50%' as separate answers on the line — pick the form the question asks for.
Fractions and decimals are the grammar of PSLE Math. Get them right and everything else reads cleaner.
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