Free worked solutions for PSLE Mathematics, with a video for every Paper 2 question we have filmed · Browse the library →
PSLE 2022 · Paper 2 · Q17 Number & Algebra · Ratio 4 marks: 1 + 2 + 1 · long answer (3 parts) difficulty 4 of 5

PSLE 2022 Paper 2, Question 17: Ratio

The answer

(a) \(15\) small cakes · (b) \(120\) cherries · (c) \(216\) cherries

PSLE 2022 Paper 2 Question 17 · Verified worked solution by the Genius Plus Academy teaching team

What this question tests

This is Question 17 of the PSLE 2022 Paper 2 Mathematics paper. It tests ratio, in the Number & Algebra strand. It is worth 4 marks: 1 + 2 + 1. Open your copy of the paper at this question, then follow our full worked solution below.

Watch the walkthrough

Video: a Genius Plus Academy teacher solving PSLE 2022 Paper 2 Question 17 Teacher video · 2022 P2 Q17

Step-by-step solution

Units table: 7 large cakes at 3u each give 21u, 15 small cakes at 2u each give 30u
Worked units table from the GPA solution for (b): cherries per cake in units, totalling 51u = 204.

(a) \(40 \div (5 + 3) = 5\); small cakes \(= 5 \times 3 = 15\). (b) Cherries per large cake \(= 3u\), per small cake \(= 2u\). 7 large cakes \(= 21u\) and 15 small cakes \(= 30u\); \(51u = 204\), so \(1u = 4\). All small cakes used \(30u = 120\) cherries. (c) Remaining large cakes \(= 25 - 7 = 18\). Each large cake needs \(3u = 12\) cherries: \(18 \times 12 = 216\) cherries.

End of Paper 2 answers.

Answer: (a) \(15\) small cakes · (b) \(120\) cherries · (c) \(216\) cherries

Same structure, different costume

A question is hard because of its structure, not its story.

Change egg tarts to badges, a tank to two tanks, a ring of card to a folded sheet, and a child sees a brand new problem. The lock underneath is the same, and so is the key. Once a student can name the structure, a whole row of questions that look different start to open the same way.

It is also where marks really leak. Across fourteen years of papers, the marks lost in PSLE math leak at the reading far more than at the arithmetic, which is exactly why recognising the structure fixes them. We call this Lock and Key: name the lock, then the key follows.

Want more questions like this, with worked solutions?

We will send a set to practise. One email, no spam.

More ratio questions, worked the same way

Same skill, different years. Each has a verified worked solution.

2025 · P1 Q26

Ratio, worked the same way.

2025 · P2 Q10

Ratio, worked the same way.

2024 · P2 Q12

Ratio, worked the same way.

2022 · P1 Q23

Ratio, worked the same way.

2022 · P2 Q5

Ratio, worked the same way.

2021 · P1 Q29

Ratio, worked the same way.

All PSLE 2022 worked solutions →

One of the 10 question types

Read a question, know the method.

The PSLE keeps testing the same 10 structures. Our PSLE Math Intensive trains the Lock and Key reflex across all ten, with 158 curated questions over two days.

Questions students ask

What does PSLE 2022 Paper 2 Question 17 test?

It is a ratio question from the Number & Algebra strand, worth 4 marks: 1 + 2 + 1.

Is there a video solution?

Yes. A Genius Plus Academy teacher works it on video above, free to watch.

Are these worked solutions free?

Yes. Every worked solution here is free to read, with no sign-up wall.

Where can I find more PSLE worked solutions?

Browse every year from 2014 to 2025 in our worked-solutions library at /resources/solutions/psle/.

See your child solve these with confidence.

Book a free trial and diagnostic. We will look at a real paper and show you exactly where the marks are going.

Book a Free Trial