Year 4 · Fractions and decimals

Adding and subtracting fractions with the same denominator

Add and subtract fractions with the same denominator

20 minutes4 checks6 exit questionsNational curriculum objective

Lesson overview

What you'll learn in this lesson

Add and subtract fractions with the same denominator

Key learning points

• Same-sized pieces
• Subtracting the same way
• Going past one whole
• Wholes in fraction clothes

This lesson at a glance

20 minutes
19 parts to scroll through
4 quick checks
No marked quiz yet
Gentle pace: short sittings with pauses

Words to know

subtractfractionsdenominatorsame-sizedpieces

Scroll down — the lesson carries on below

Part 1 of 19 · Discover5%

Watch & discover

Part 1 of 19

Watch first

Adding and subtracting fractions with the same denominator

See how a fraction and a decimal can be exactly the same amount.

Do it for real

The practicals below use what the film shows, with a full method you can follow at home.

Fair shares with water

In a nutshell

Add and subtract fractions with the same denominator

What you already know

Part 2 of 19

Before we start

What you already know

You know what the numerator and denominator of a fraction mean.

Key words

Part 3 of 19

Key words

Words you'll need today

numerator: The top number — how many pieces you have.
denominator: The bottom number — how many pieces the whole is cut into.
improper fraction: A fraction where the top is bigger than the bottom, like 7/5.

Learning cycle

Part 4 of 19

Learning cycle 1 of 2

Part 1 — Counting pieces

A short piece of teaching, then a check to make sure it has landed.

Explore the idea

Part 5 of 19

Learn

Same-sized pieces

2/7 + 3/7 = 5/7. Two sevenths plus three sevenths is five sevenths, because every piece is one seventh. The denominator does not change — you are not making more pieces, just collecting them.

Explore the idea

Part 6 of 19

Learn

Subtracting the same way

6/9 − 4/9 = 2/9. Take four pieces away from six and two are left. Again the 9 stays put. If you find yourself subtracting the bottoms too, stop and picture a chocolate bar cut into nine.

Quick check

Part 7 of 19

Quick check

3/8 + 4/8 =

Quick check

Part 8 of 19

Quick check

9/11 − 5/11 =

Reset break

Part 9 of 19

Pause

That's sitting 1 of 2 done

Stretch, get a drink, look out of the window. There is no timer and nothing is counting down — your place is saved, so you can come back in five minutes or tomorrow.

Stop here for now

Learning cycle

Part 10 of 19

Learning cycle 2 of 2

Part 2 — Past the whole

A short piece of teaching, then a check to make sure it has landed.

Explore the idea

Part 11 of 19

Learn

Going past one whole

3/5 + 4/5 = 7/5. That is more than a whole, and it is fine to leave it as 7/5, or write it as 1 2/5 because five fifths make one whole with two fifths spare.

Explore the idea

Part 12 of 19

Learn

Wholes in fraction clothes

1 whole = 4/4 = 8/8 = 10/10. That helps with 1 − 3/8: rewrite the 1 as 8/8, so 8/8 − 3/8 = 5/8. This trick appears constantly in tests.

Quick check

Part 13 of 19

Quick check

2/6 + 5/6 =

Quick check

Part 14 of 19

Quick check

1 − 2/5 =

Common mix-ups

Part 15 of 19

Common mix-ups

Things people often get wrong

Adding the denominators: 2/7 + 3/7 = 5/14.
Thinking 7/5 must be wrong because the top is bigger.
Forgetting to rewrite 1 as a fraction before subtracting.

Challenge round

Part 16 of 19

Game · Sort it

Which of these are true?

Drag each card into the right column. Tap a card first if dragging is fiddly.

True

Not true

Challenge round

Part 17 of 19

Game · Fill the gaps

Finish the sentences

Choose the word that belongs in each gap.

The ____ does not change — you are not making more pieces, just collecting them.

Take four ____ away from six and two are left.

Mastery quiz

Part 18 of 19

No quiz for this one

This lesson has no marked quiz attached yet.

Lesson round-up

Part 19 of 19

Lesson round-up

Ready when you are

Quiz score

Not sat

Games

Not played

Points this lesson

Best run

0 in a row

Luna: 0 out of 4 on the practice checks. Only if you feel up to it — one more?

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Do the work

Your written work for this lesson

This is the part you'd do in your book at school. Pick the pieces below, write here or on paper, and photograph anything you draw or work out.

Article

The cost of a school trip

A school is planning a trip to a wildlife park. The coach costs £480 however many people go. Entry costs £9.50 for each pupil and each adult goes free. The school says every pupil must pay the same amount, and the trip must not lose money.

If 60 pupils go, the coach works out at £8 each, so the total for each pupil is £17.50. If only 40 pupils go, the coach works out at £12 each, so the price rises to £21.50. The teacher explains that the coach is a fixed cost and the entry is a cost per person — which is why the price per pupil changes when the number changes.

The school decides to charge £20 and to use anything left over for a second trip later in the year.

Written for Good Learning Co.

Reading questions

Work out the total cost of the trip if 50 pupils go.
Show why the price per pupil falls when more pupils go, using numbers.
At £20 each, how many pupils must go before the trip makes money? Show your working.

Working out
Working out
Do the practice questions on paper, showing every step — not just the answer. Mark them yourself and circle anything you got wrong.
10–15 questions
Worked example, explained
Writing
Copy one question out and write underneath, in words, why each step works.
1 question, 4–5 sentences
Problem in words
Working out
Write your own real-life problem that uses today's method, then solve it.
1 problem + solution

Write your answer, notes or working here

Saved as you type.

Photos of paper work, diagrams or working outHow many minutes did the written work take?

Part 1 of 19 · Watch & discover

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