Primary Math: Fractions Made Simple for Singapore Students

Quick answer

Fractions can feel tricky, especially when you're staring at a PSLE question and your mind goes blank. But don't worry! After reading this, you'll know which mistakes to avoid and have a few simple tricks up your sleeve to tackle any fraction problem with confidence.

What you need to know

Fractions are a way to show parts of a whole. Imagine slicing a pizza into equal pieces. Each piece is a fraction of the pizza. The top number (numerator) tells you how many pieces you have, and the bottom number (denominator) tells you how many equal pieces the pizza is cut into.

Common Fraction Mistakes

Most students trip up on fractions because they rush through the steps or don't fully understand what the numbers mean. Here are three common traps and how to sidestep them:

1. Adding and Subtracting with Different Denominators

   • Always find a common denominator first.
   • Why: Without the same denominator, you're not comparing the same-sized pieces.

2. Multiplying Fractions

   • Multiply the numerators, then the denominators.
   • Why: This gives you the total number of smaller pieces.

3. Dividing Fractions

   • Flip the second fraction and multiply.
   • Why: Flipping turns division into multiplication, which is easier to handle.

Quick check

Try these to see if you've got it:

1. Add $\frac{1}{4}$ and $\frac{1}{3}$.
2. Multiply $\frac{2}{3}$ by $\frac{4}{5}$.
3. Divide $\frac{3}{4}$ by $\frac{2}{3}$.

Answers:

1. $\frac{7}{12}$
2. $\frac{8}{15}$
3. $\frac{9}{8}$

Revision checklist

• Check denominators: Always make them the same before adding or subtracting.
• Simplify: After multiplying or dividing, simplify your fraction.
• Label your steps: In exams, writing each step helps you avoid careless errors.

Exam tip

In exams, neatness counts. Write fractions clearly, and always double-check your answers. If you rush, you might miss a step and lose marks. Remember, questions often have clues on what to do next.

Question

Sam has $\frac{3}{4}$ of a chocolate bar and gives $\frac{1}{3}$ to his friend. How much does he have left?

Solution

Step 1: Find a common denominator for $\frac{3}{4}$ and $\frac{1}{3}$.
Why: You need the same-sized pieces to subtract them.

Step 2: Convert $\frac{3}{4}$ to $\frac{9}{12}$ and $\frac{1}{3}$ to $\frac{4}{12}$.
Why: Now you can subtract since they have the same denominator.

Step 3: Subtract $\frac{9}{12} - \frac{4}{12} = \frac{5}{12}$.
Why: This shows the chocolate Sam has left.

Quick summary

• Always find a common denominator for addition and subtraction.
• Multiply numerators and denominators separately.
• Flip and multiply for division.
• Simplify answers to the smallest terms.
• Write fractions clearly in exams to avoid mistakes.

FAQ

Q: Why do I need a common denominator?
A: Without it, you're comparing different-sized pieces, which doesn't work for addition or subtraction.

Q: Can I multiply directly without simplifying first?
A: Yes, but simplifying at the end is easier for most students.

Q: Why flip the second fraction when dividing?
A: Flipping turns division into multiplication, which is simpler to solve.

Q: How can I practice more effectively?
A: Short, daily revision is key. Try a few problems each day instead of cramming.

Related Topics You Should Learn Next

• Primary Mathematics Fractions: Your Complete Guide to Avoiding Common Mistakes
• Primary Mathematics: Fractions Explained Simply for Singapore Students
• Primary Fractions: Avoid These 5 Common Mistakes in Singapore Exams
• Primary Mathematics: Scoring High in Fractions Without Running Out of Time