Fractions are at the heart of many important Math skills, and getting the hang of adding and subtracting fractions early on is key. If your child doesn’t fully grasp fractions in Primary 2, it can make things harder as they move through Primary 3, 4, and 5, and when it’s time for the PSLE.

A strong foundation in Fractions will give them a huge advantage in these years.

Whether it’s learning to work with fractions with same denominators, different denominators, or mixed numbers, mastering these skills will help your child solve problems like subtracting fractions, finding common denominators, and even simplifying improper fractions. By building confidence with these core concepts, they’ll be ready to tackle more advanced Math down the road!

Fractions are a critical topic your child will begin learning from Primary 2. Here is an overview of how their understanding of fractions will grow over the next few years:

Primary 2: Your child will start with simple addition and subtraction of like fractions (fractions with the same denominator). They will also learn how to compare and order fractions, which builds their confidence in working with parts of a whole.

Primary 3: The focus shifts to equivalent fractions and simplifying fractions. They will continue practicing addition and subtraction of like fractions, but with more emphasis on solving word problems. These problems help link what they have learned to real-life situations.

Primary 4: This is when they will explore the relationship between mixed numbers and improper fractions. They will also learn about fractions as part of a set of objects (e.g. dividing a group of items into equal parts). Addition and subtraction become more complex as they start working with fractions with different denominators, requiring a solid understanding of multiplication and number sense.

Primary 5: Your child will advance to dividing whole numbers and expressing the answer as a fraction. They will also convert fractions to decimals and perform addition, subtraction, and multiplication of fractions, all without a calculator. This year, they will be introduced to ratio and percentage as well and they will learn how these two new topics will connect with fractions. This linkage between fractions, ratio, and percentage is crucial as these topics form about 60% of the PSLE Math paper.

What is a Fraction?

Numerator: The numerator is the top number of a fraction. It tells us how many parts we are considering out of the whole. For example, in the fraction 34, the numerator is 3, meaning we are focusing on 3 parts of the whole.

Denominator: The denominator is the bottom number of a fraction. It shows the total number of equal parts the whole is divided into. In the same fraction 34, the denominator is 4, meaning the whole is divided into 4 equal parts.

Think of it as slicing a pizza:

• If you cut the pizza into 8 slices, 8 becomes the denominator (the total number of parts).
• If you eat 3 slices, 3 is the numerator (the part you ate). So, you ate 38 of the pizza.

How Do You Add/Subtract Fractions (Step-by-Step)?

What is the rule for adding/subtracting fractions?

Addition and Subtraction of Like Fractions (Same Denominator)

For addition and subtraction of like fractions (fractions with the same denominator), the process is simpler:

Addition of Like Fractions:

1. Keep the Denominator the Same: Since the denominators are already the same, you do not need to find a common denominator.
2. Add the Numerators: Add the top numbers (numerators) together while keeping the denominator unchanged.
3. Simplify if Necessary: If the result can be simplified, reduce the fraction to its simplest form.

Subtraction of Like Fractions:

1. Keep the Denominator the Same: Since the denominators are already the same, you do not need to find a common denominator.
2. Subtract the Numerators: Subtract the top numbers (numerators) while keeping the denominator unchanged.
3. Simplify if Necessary: Reduce the fraction to its simplest form if possible.

In summary, for addition and subtraction for like fractions, you simply work with the numerators while keeping the denominator the same.

Addition and Subtraction of Unlike Fractions (Different Denominators)

For addition and subtraction of unlike fractions (fractions with different denominators), the process involves a few more steps:

Addition of Unlike Fractions:

1. Find a Common Denominator: Determine the least common multiple (LCM) of the denominators to use as the common denominator.
2. Convert Fractions to the Common Denominator: Adjust each fraction so that both have the common denominator.
3. Add the Numerators: After converting to the common denominator, add the numerators together while keeping the common denominator.
4. Simplify if Necessary: Reduce the resulting fraction to its simplest form if possible.

Subtraction of Unlike Fractions:

1. Find a Common Denominator: Determine the least common multiple (LCM) of the denominators to use as the common denominator.
2. Convert Fractions to the Common Denominator: Adjust each fraction so that both have the common denominator.
3. Add the Numerators: After converting to the common denominator, add the numerators together while keeping the common denominator.
4. Simplify if Necessary: Reduce the resulting fraction to its simplest form if possible.

Fractions of a Set

Example 1:

Circle \(\frac{1}{2}\) of the circles

\(\frac{1}{2}\) of 16 is 8.
\(\frac{1}{2}\) x \(\frac{16}{1}\) = 8 (Ans)

Example 2:

\(\frac{1}{2}\) of the circles are shaded.

How many circles are shaded?

\(\frac{1}{2}\) x \(\frac{12}{1}\) = 6 (Ans)

Addition and Subtraction of Mixed Numbers

Addition of Mixed Numbers:

1. Add the Whole Numbers: Start by adding the whole number parts of each mixed number together.
2. Add the Fractions: Next, add the fractional parts. If the fractions have the same denominator, simply add the numerators and keep the denominator the same. If the fractions have different denominators, first find a common denominator, convert the fractions to this common denominator (LCM), and then add them.
3. Simplify the Fraction (if needed): If the resulting fraction can be simplified, do so. Sometimes the fraction part of your answer may be an improper fraction (where the numerator is larger than the denominator).
4. Combine the Whole Number and Fraction: If you have an improper fraction as a result of the addition of the fractions, convert it into a mixed number.

Subtraction of Mixed Numbers:

1. Subtract the Whole Numbers: Start by subtracting the whole number parts of each mixed number together.
2. Subctract the Fractions: Next, subtract the fractional parts. If the fractions have the same denominator, simply subtract the numerators and keep the denominator the same.
   If the fractions have different denominators, first find a common denominator, convert the fractions to this common denominator (LCM), and then subtract them.
3. Simplify the Fraction (if needed): If the resulting fraction can be simplified, do so. Sometimes the fraction part of your answer may be an improper fraction (where the numerator is larger than the denominator).
4. Combine the Whole Number and Fraction: If you have an improper fraction as a result of the addition of the fractions, convert it into a mixed number.

Multiplying Proper or Improper Fraction by a Whole Number

1. Multiply the Numerator by the Whole Number:
2. Multiply the denominator by 1 as 2 whole is the same as 21.
3. Simplify the Fraction (if needed)

Multiplying Two Improper fractions

1. Multiply the Numerators: Multiply the numerator of the first improper fraction by the numerator of the second improper fraction.
2. Multiply the Denominators: Multiply the denominator of the first improper fraction by the denominator of the second improper fraction.
3. Simplify the Fraction (if needed)

Multiplying Mixed Number with a Whole Number

1. Convert the Mixed Number to an Improper Fraction:
2. Multiply the Improper Fraction by the Whole Number:
3. Simplify the Fraction (if needed)

Dividing Fraction with a Fraction

KCF, or Keep, Change, Flip, is a handy acronym for dividing fractions. Here is how it works:

1. Keep the first fraction as it is.
2. Change the division sign to multiplication.
3. Flip the second fraction to its reciprocal.

Want to know how your child can build a solid foundation in Math?

It all starts with good problem-solving techniques and a strong concept understanding! 💪This can be achieved through our primary math tuition programme which provides engaging instruction tailored to your child’s needs, setting them up for success using our proven methods. Book a FREE trial lesson to see firsthand how your child can excel in math. 📈

Ready to go further? We offer a range of supplementary courses, which includes the following:

• P5 Exam Preparatory Course (EPC)
• PSLE Preparatory Courses (PPC)
• PSLE Intensive Course (PIC)
• Headstart and holiday programmes (M.A.P.)

If you’ve got a burning question, feel free to reach out to us today!