Subtracting fractions with same and different denominators, including from whole numbers.
Where your child meets this in real life: Finding remaining quantities (how much pizza is left after eating some)
SEAGReady breaks subtract fractions into 3 steps, taught in order so each skill builds on the last.
Master same denominator subtraction skills
Master different denominator subtraction skills
Master subtracting from whole numbers skills
Three free sample questions from our subtract fractions course. Every question comes with a full explanation, and hints that guide without giving the answer away.
Ciara has 7/8 of a chocolate bar. She gives 3/8 to her brother Sean. What fraction of the chocolate bar does Ciara have left?
Answer: A. 4/8
Both fractions have denominator 8 (eighths). Subtract the numerators: 7 - 3 = 4 Keep the denominator the same: 8 Answer: 4/8 of the chocolate bar
Stuck? Start here: Both fractions have the same denominator (8). What does that tell you?
Oisin had 3/4 of a litre of juice. He drank 1/2 of a litre. How much juice does Oisin have left?
Answer: A. 1/4 of a litre
The denominators are different (4 and 2). Convert 1/2 to quarters: 1/2 = 2/4 Now subtract: 3/4 - 2/4 = 1/4 Answer: 1/4 of a litre
Stuck? Start here: The denominators are different (4 and 2). Can you make them the same?
Sean has 2 pizzas. He gives 3/4 of a pizza to his friend. How much pizza does Sean have left?
Answer: A. 1 1/4 pizzas
Convert 2 to quarters: 2 = 8/4 Subtract: 8/4 - 3/4 = 5/4 Convert to mixed number: 5/4 = 1 1/4 Answer: Sean has 1 1/4 pizzas left
Stuck? Start here: First, write 2 as a fraction with denominator 4.
This is the exact interactive worked example your child sees in SEAGReady. Step through it and watch the method build up.
Aoife has ⁵⁄₈ of a pizza left over from dinner. She eats ²⁄₈ for breakfast.
What fraction of the pizza does Aoife have now?
⁵⁄₈ − ²⁄₈
Step 1 of 4
Aoife has ⁵⁄₈ of a pizza left over from dinner. She eats ²⁄₈ for breakfast.
What fraction of the pizza does Aoife have now?
Aoife has ³⁄₈ of the pizza left.
The key insight: When denominators are the same, just subtract the numerators and keep the denominator!
Watch out: ⁵⁄₈ − ²⁄₈ = ³⁄₀. You subtract the numerators but keep the denominator - never subtract denominators!
These are the misconceptions we see most often in subtract fractions, including the ones our practice questions are specifically designed to catch.
Struggling with subtract fractions? The real gap is often in one of these earlier topics.
SEAGReady finds the exact step where your child gets stuck, teaches it with worked examples like the one above, and brings it back for review so it sticks.