The Rules of Engagement

PSLE Math Paper 1 is worth 45% of your total score. It consists of:

• Booklet A: 15 Multiple Choice Questions (20 marks)
• Booklet B: 15 Short Answer Questions (25 marks)
• Time: 1 Hour

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Mental Math Hacks (Your Secret Weapon)

Since you can’t click buttons, you need to upgrade your mental software.

1. Memorize Key Conversions

Don’t waste time dividing $3 \div 8$ in long division. Memorize these common fractions to decimals:

Fraction	Decimal	Percentage
$1/2$	$0.5$	$50\%$
$1/4$	$0.25$	$25\%$
$3/4$	$0.75$	$75\%$
$1/5$	$0.2$	$20\%$
$1/8$	$0.125$	$12.5\%$
$1/10$	$0.1$	$10\%$

2. The “Distribution” Method

Multiplying big numbers? Break them apart.

$12 \times 25$ $= (3 \times 4) \times 25$ $= 3 \times (4 \times 25)$ $= 3 \times 100$ $= 300$

Values like 25, 50, and 125 are your friends. Look for them!

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Booklet A Strategies: The Art of Elimination

In Booklet A, the answer is right in front of you. You don’t always need to solve the question from scratch; you just need to identify the correct option.

1. The Elimination Method

Remove options that are obviously wrong (Ridiculous answers).

2. Substitution Strategy

When finding Unknowns in Algebra or Equations, you can plug the options back into the question.

Question: If $3y + 5 = 26$, what is $y$? Options: (1) 5, (2) 6, (3) 7, (4) 8

Instead of solving algebra:

• Test Option (1): $3 \times 5 + 5 = 20$ (Incorrect)
• Test Option (3): $3 \times 7 + 5 = 26$ (Correct!)

3. Estimation Check

Before calculating, mentally estimate the answer.

• $49 \times 21 \approx 50 \times 20 = 1000$
• If your calculation gives 10,290, you know you made a mistake instantly.

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Booklet B Strategies: Precision is Key

In Short Answer Questions, there are no options to guide you. You must be precise.

1. Pattern Recognition

For questions asking for the 100th term or shape, do not list everything out.

1. Find the Group: Identify the repeating block (e.g., A, B, C, A, B, C… group size is 3).
2. Divide: $100 \div 3 = 33 \text{ R } 1$.
3. Remainder Rule: Remainder 1 means it is the 1st item in the group (A).

2. Working Backwards

If a question gives you the Final Result and asks for the Start Number, reverse the operations.

• “Add 5” becomes “Subtract 5”
• “Multiply by 2” becomes “Divide by 2”

3. The “Unit Trap”

This is the #1 cause of lost marks in Paper 1.

• Question asks for answer in litres, but you calculated in ml?
• Question asks for answer in minutes, but you calculated in hours?

4. The “Impossible Answer” Check

Before you move to the next question, ask: “Is this answer impossible?”

• Did you find the speed of a car to be $1200 \text{ km/h}$? (Too fast!)
• Did you find the number of students to be $35.5$? (People can’t be decimals!)
• Did you find Alice’s age to be $150$? (Too old!)

If the answer feels wrong, it probably is. Recalculate.