P6 ratio problem sums with worked answers
Ratio problem sums reward a child who knows what stays the same. When one person gives some to another, the total is unchanged, and your child needs to build the units around that before finding any amount.
What the PSLE tests in ratio
- Writing ratios of two or three quantities and simplifying them
- Equivalent ratios and finding a missing term
- Finding a quantity given the ratio and the total or the difference
- Before-and-after problems where one quantity or the total stays the same
- Connecting ratio with fractions, for example 3 : 5 as 3/8 of the total
Where children lose the most marks
- Transfer questions where one person gives some to another and the total stays the same
- Problems where both quantities change and the ratios must be matched to a common number of units
- Questions that ask for the total or the other person's share after finding one unit
A PSLE-style question, worked
The ratio of Mei's stickers to Jun Wei's stickers was 5 : 3. After Mei gave 24 stickers to Jun Wei, they had the same number of stickers. How many stickers did they have altogether?
- Before: Mei 5 units, Jun Wei 3 units, total 8 units
- The total stays the same, so after: Mei 4 units, Jun Wei 4 units
- Mei gave 5 units − 4 units = 1 unit
- 1 unit = 24 stickers
- Total = 8 units = 8 × 24 = 192 stickers
Why 96 stickers is wrong: The child set the 24 stickers equal to the difference of 2 units, so 1 unit = 12 and 8 units = 96. Mei only gives away 1 unit; the gap of 2 units closes because Jun Wei also gains that unit.
Free PSLE ratio questions with answers
Careless mistakes to watch in ratio
Stopped at one part in ratio
Your child finds 1 unit in a PSLE ratio question and writes it as the answer. Why children stop early and simple ways to fix it at home.
See the fix →Calculation slip
Your child uses the right method but slips on the arithmetic, like a missing zero in long division. How to spot calculation slips and cut them down.
See the fix →Questions parents ask
What kinds of ratio questions come out in the PSLE?
Ratio commonly appears in Paper 2 structured questions, often as before-and-after or transfer problems, and in shorter questions on simplifying or equivalent ratios.
Should my child use units or bar models for ratio problem sums?
Both are accepted. Units are faster once your child can see which quantity stays the same, and a bar model is the clearest way to find it.
Do ratio answers need to be in simplest form?
When a question asks for a ratio, give it in simplest form unless told otherwise. 10 : 6 should be written as 5 : 3.
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