Take a moment to think: what is a smart first step, and what does the bottom number of the fraction tell us to do?
Here is a question to warm us up. Three quarters of the class of 20 walk to school. How many pupils is that? Hands up if you have a way to start.
Take three hands-up answers, not open call-outs. Give five seconds of quiet think-time first. Listen for anyone who says split 20 into 4 groups — that is exactly the move the lesson builds on. Don't confirm or work it out yet; just gather ideas and move to the model.
The bars show four fraction problems worked one at a time. Watch how each whole splits into equal parts, and follow the two steps: divide by the bottom, then multiply by the top. The last one turns it around — we know a part and build back to the whole.
Keep the same rhythm every time: divide by the bottom to find one part, multiply by the top for the parts we want.
3/4 of 20: point to one shaded part, ask what it is worth (5) before the total. 20 divided by 4 is 5, 3 times 5 is 15.
2/3 of 18: smaller bottom means fewer, bigger parts. Parts of 6, take 2, that is 12.
5/8 of 40: take the prediction first — more or less than half of 40? More than half, so over 20. Then check: 40 divided by 8 is 5, 5 times 5 is 25. This is the key one — let them sense the size before the arithmetic.
Working backwards: reverse move on the bar. Class is 5 equal parts, 2 parts (boys) are worth 12. Ask what one part is worth: 12 divided by 2 is 6. All 5 parts make 5 times 6 is 30. We know a part, find one part, build the whole. They meet this again in the stretch problem later.
Each time we split the whole bar into equal parts, find what one part is worth, then take the parts we need.
Today we work through these together on the ratio bars: 3/4 of 24, then 2/5 of 35, then 5/6 of 48.
We'll say each first step out loud before anyone touches the board: how many parts, and what is one part worth?
Try Together: model the first prompt with the class, then have pupils drive the rest, agreeing or correcting out loud.
Reset the bar for each prompt, set Parts taken and Parts left to match the fraction and type the new whole amount: 3 taken and 1 left with whole 24, then 2 taken and 3 left with whole 35, then 5 taken and 1 left with whole 48. For each amount, ask two questions before building: how many parts do we split into? and what is one part worth? Only then take the numerator's share. 3/4 of 24 splits into 4 parts of 6 (answer 18); 2/5 of 35 splits into 5 parts of 7 (answer 14); 5/6 of 48 splits into 6 parts of 8 (answer 40). Rotate three pupils to drive the bar. If a pupil multiplies before dividing, revoice: first find one part, then take the parts we want.
In your maths copy, work each of these problems. For every one, show your two steps clearly: first divide by the bottom to find one part, then multiply by the top to find the answer. Box your answer.
Walk the room glancing that both steps are written, not just the final answer — this is whole-class copybook practice, not marking. Nudge anyone who wrote only the answer to show the divide step underneath.
Here are today's challenges: 3/4 of 24 sweets, then 2/3 of a €30 voucher, then 5/6 of 48 minutes. Each one splits the whole into equal parts, then takes the parts the fraction asks for. We finish with a stretch: working backwards from the parts to find the whole.
Class Challenge: pupils take turns at the board, check each answer, and the class confirms before moving on. Keep the board work brisk rather than over-explaining.
Core answers in order: 3/4 of 24 = 18; 2/3 of €30 = €20; 5/6 of 48 min = 40 min. For the €30 and 48-minute bars, the interactive shows the proportion (2 of 3 parts, 5 of 6 parts); the real amounts are named in the prompt, so say the value of one part aloud (€10, then 8 minutes) as you build.
Then work the reverse stretch on the board with the class, exactly as it was modelled in Watch and Notice — 2 parts = 12, so one part = 6, and 5 parts = 30 pupils. Revoice the reverse move: we already know two parts are worth 12, so we work back to one part, then build up to the whole. Let a confident pupil lead the reverse one.
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