Watch the walkthrough
Teacher video · 2022 P2 Q7
The answer
(a) \(20\) min · (b) 09 00 to 09 05 and 09 15 to 09 20 · (c) \(0\) °C per minute
PSLE 2022 Paper 2 Question 7 · Verified worked solution by the Genius Plus Academy teaching team
What this question tests
This is Question 7 of the PSLE 2022 Paper 2 Mathematics paper. It tests data: line graph, in the Statistics strand. It is worth 3 marks: 1 + 1 + 1. Open your copy of the paper at this question, then follow our full worked solution below.
Watch the walkthrough
Teacher video · 2022 P2 Q7
(a) The temperature reaches 50°C at 09 10 and stays below it until 09 30: \(20\) minutes.
(b) Drops per 5-min interval: \(20, 25, 15, 20, 5, 0\), the equal drops (20°C) are 09 00 to 09 05 and 09 15 to 09 20.
(c) From 09 25 to 09 30 the temperature is constant: \(0 \div 5 = 0\) °C/min.
Answer: (a) \(20\) min · (b) 09 00 to 09 05 and 09 15 to 09 20 · (c) \(0\) °C per minute
Same structure, different costume
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.
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One of the 10 question types
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.
It is a data: line graph question from the Statistics strand, worth 3 marks: 1 + 1 + 1.
Yes. A Genius Plus Academy teacher works it on video above, free to watch.
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