Profit, Loss and Best-value Shopping

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1 Getting Started
2 Watch and Notice
3 Try It Together
4 Work It in Your Copy
5 Class Challenge
Pupil practice

1 - Getting Started ~4 mins

Illustration for Getting Started Here are two ways to buy the same yoghurts: a 6-pack for €2.40, or single pots at 45c each. Hands up: which one do you think is the better buy? And how could you actually prove it, rather than just guessing?

Teacher Notes

Take three hands-up answers, not open call-outs. Do not settle which is cheaper yet — the point is that gut feeling is unreliable and we need a fair way to compare. Hold that tension into Watch and Notice.

👇 Mark your steps as done as you complete them.

+5 XP

2 - Watch and Notice ~9 mins

We work through four shelf-tag comparisons together. For each pair, share the pack price out to find the cost of just one, the unit price, and say which side wins and why. On the last one, predict the winner before the working is shown. Then we switch to a fundraising stall and look at profit and loss.

Teacher Notes

Card 1: 6-pack €2.40 ÷ 6 = 40c each, single 45c — 6-pack wins.

Card 2: €1.80 ÷ 4 = 45c each vs €2.50 ÷ 5 = 50c each — 4-pack wins.

Card 3 (a tie): €2.40 ÷ 6 = 40c and €3.20 ÷ 8 = 40c — same value; get a guess first, most expect the 8-pack to win because it is bigger.

Card 4: hold the reveal — 12-pack looks the obvious bargain but the 5-pack offer beats it by 8 c a bag. The whole point: lowest unit price wins, not biggest pack.

Stall is a fresh idea, not a fifth card. Profit = selling above cost: badge costs €2, sells €3.20, profit €1.20. Loss = selling below cost: scarf costs €6, sells €5, loss €1. Say both rules as the figures build. The shop set that crisp offer price to sell more — that is how a stall makes profit.

👇 Mark your steps as done as you complete them.

+10 XP

3 - Try It Together ~10 mins

Key point

Remember: profit is selling above what something cost, and loss is selling below what it cost.

We work the first pair on the interactive together, then work the rest on the board:

On the interactive: €3.00 for 5 bars vs €4.55 for 7 bars
On the board: €4.50 for 3 bottles vs €7.00 for 5 bottles
On the board: Stall — a badge bought for €2, sold for €3.20
On the board: Stall — a scarf bought for €6, sold for €5

Which is the better buy?

Teacher Notes

Talk this one through together — pupils take turns at the board and the class agrees or corrects out loud.

Timing across the 10 minutes: spend about 3 minutes on the cereal-bars pair using the interactive, about 3 minutes on the bottles pair worked on the board, and about 4 minutes on the two profit-and-loss cases worked as words on the board.

On the interactive: €3.00 ÷ 5 = 60c a bar beats €4.55 ÷ 7 = 65c, so the 5-pack wins. On the board: €4.50 ÷ 3 = €1.50 against €7.00 ÷ 5 = €1.40, so the 5-pack of bottles wins. For the profit-and-loss cases, work them on the board as words: badge — cost €2, sale €3.20, profit €1.20; scarf — cost €6, sale €5, loss €1. Watch for pupils who subtract the wrong way round on the loss.

+10 XP

4 - Work It in Your Copy ~3 mins

COPYBOOK MOMENT

First we work one pair together on the board so everyone sees the full method. Then in your maths copy, for each pair of shopping options write the unit price of both and circle the better value. After that, for each profit-and-loss example write three things one under the other:

Cost
Sale
Profit or Loss

Work out and label each one.

Board example first: €2.80 for 4 apples against €3.60 for 6 apples.

In your copy, pairs:

€4.00 for 8 yoghurts vs €2.70 for 5 yoghurts
€6.00 for 5 notebooks vs €3.60 for 4 notebooks

In your copy, profit and loss:

A badge costs €1.50 and sells for €2.25
A scarf costs €5 and sells for €4.20

Teacher Notes

Board demo first (about 2 minutes): €2.80 ÷ 4 = 70c each; €3.60 ÷ 6 = 60c each, so the 6-pack wins. Say the rule once: divide pack price by number of items, lowest unit price wins.

Copy answers: pair 1, €4.00 ÷ 8 = 50c, €2.70 ÷ 5 = 54c, 8-pack wins. Pair 2, €6.00 ÷ 5 = €1.20, €3.60 ÷ 4 = 90c, 4-pack wins (smaller pack better value). Badge: cost €1.50, sale €2.25, profit 75c. Scarf: cost €5, sale €4.20, loss 80c.

Walk the room. Watch for dividing the wrong way round and for subtracting sale from cost on the loss. No individual marking, this is whole-class copybook practice, not assessment.

+10 XP

5 - Class Challenge ~8 mins

Key point

Today we work through four comparisons on the board in order: a 6-pack against a 4-pack of the same drink, then two washing-powder boxes of different sizes, then a 20-pack of pens against a 10-pack, and finally a battery-pack twist.

After the four comparisons, we work a total-profit sum together on the board: a fundraising stall buys 20 wristbands at €2 each and sells them all at €3.50 — what is the total profit?

Best value and total profit

Teacher Notes

This is the practice round — 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.

Four challenges in order: sports drink, washing powder, pens, then the battery twist. For each, divide to the unit price, let the class predict the winner, and let Check confirm. The pens round (€8.00 ÷ 20 = 40c a pen against €4.20 ÷ 10 = 42c) keeps the pace up before the climax. On the washing powder, €5.00 ÷ 10 = 50c a wash against €3.36 ÷ 7 = 48c a wash, so the smaller box wins. The fourth is the climax — €7.20 ÷ 12 = 60c against €2.75 ÷ 5 = 55c, so the 5-pack really is cheaper per battery even though the box is smaller. For the total-profit stretch, work it on the board alongside: buy 20 at €2 = €40 spent; sell 20 at €3.50 = €70 taken in; profit = €70 − €40 = €30. Ask what would change if three wristbands were left unsold.

+15 XP

Pupil practice

Module 6 · Time and Money Shape & Space

Lesson 66 · Profit, Loss and Best-value Shopping

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Teacher Class Feed

1 - Getting Started ~4 mins

2 - Watch and Notice ~9 mins

3 - Try It Together ~10 mins

Which is the better buy?

4 - Work It in Your Copy ~3 mins

5 - Class Challenge ~8 mins

Best value and total profit

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