Are You a Smart Shopper?
In a town there are three supermarkets which each have a special deal on some products. If you bought all your shopping in one shop, which would be the cheapest?
Problem
Are You a Smart Shopper? printable sheet
In a town there are three supermarkets: Gary's Groceries, Fiona's Foods and Paul's Provisions.
This week there are special deals on some products at all three shops.
At Gary's Groceries, items are being sold at discount prices.
At Fiona's Foods, you can buy items which are larger than usual.
At Paul's Provisions, there are some "buy one get one free" deals.
Have a look:
Gary's Groceries | |||||
|---|---|---|---|---|---|
| Item | Image
Biscuits | Image
Oven chips | Image
Crisps | Image
Lemonade | Image
Sausages |
| Quantity | 7 pack | 1.8kg | 6 pack | 2 litres | 8 pack |
| Original price | 94p | £1.60 | £1.20 | 55p | £1.85 |
| Special offer | 50% off | 25% off | 35% off | 20% off | 40% off |
Fiona's Foods | |||||
|---|---|---|---|---|---|
| Item | Image
Biscuits | Image
Oven chips | Image
Crisps | Image
Lemonade | Image
Sausages |
| Special offer | 40% extra free | 12.5% extra free | 20% extra free | 25% extra free | 60% extra free |
| New quantity | 7 pack | 1.8kg | 6 pack | 2 litres | 8 pack |
| Price | 42p | £1.55 | 99p | 43p | £1.04 |
Paul's Provisions | |||||
|---|---|---|---|---|---|
| Item | Image
Biscuits | Image
Oven chips | Image
Crisps | Image
Lemonade | Image
Sausages |
| Quantity | 7 pack | 1.8kg | 6 pack | 2 litres | 8 pack |
| Price | 89p | £2.49 | £1.59 | 90p | £2.04 |
| Special offer | Buy one get one free | Buy one get one free | Buy one get one free | Buy one get one free | Buy one get one free |
If you shopped at Gary's Groceries, how much would you actually pay for each item? So how much money have you saved on each?
Here is your shopping list:
- 2 bottles of lemonade (2 litre size)
- 1 6 pack of crisps
- 24 sausages
- 1 bag of chips (1.8kg size)
If you bought all the items in one shop, where would be the cheapest?
If you could buy the items from different shops, how would you do it to spend the least amount of money?
Apart from the cost, can you think of any other advantages or disadvantages of buying these items at just one shop?
You have £10.70 to spend on a party meal for you and nine friends. Here's your shopping list:
- 4 bottles of lemonade (2 litre size)
- 4 packets of sausages (8 pack size)
- 2 bags of chips (1.8kg size)
- 2 bags of crisps (6 pack size)
- 2 packets of biscuits (7 pack size)
How can you do this without going over your budget?
How many different ways are there?
Which shop offers best value for money on each item?
What sorts of things do you need to take into account to answer this?
Is the "buy one get one free" deal at Paul's Provisions the same as a 50% off deal?
Student Solutions
Mollie of St.Michael's C.of.E Primary School, Sandhurst, laid out her method very carefully:
Firstly I needed to work out all the actual prices for all the items at Gary's Groceries:
Chocobiscuits= 94p- 50%= 47p
Oven Chips= £1.60 - 25%= £1.20
Crisps= £1.20 - 35% = 70p
Lemonade= 55p - 20% = 44p
Sausages= £1.85 - 40% = £1.11
Secondly I had to work out how much was saved on each item:
Chocobiscuits= 47p
Oven Chips= 40p
Crisps= 42p
Lemonade= 11p
Sausages= 74p
Mrs Lydford's groups of Balgowan Primary School then found the cost of the shopping list at each store:
Gary's Groceries= 2 x 44p + 1 x 78p + 3 x 111p + 1 x 120p = 619p = £6.19
Fiona's Food's= 2 x 43p + 1 x 99p + 3 x 104p + 1 x 155p = 650p = £6.52
Paul's Provision's= 1 x 90p (using buy one get one free) + 1 x 159 + 2 x 204 (two bought at buy one get one free, the third bought at full price) + 1 x 249p = 906p = £9.06
Gary's Groceries would be the cheapest place to buy the whole shopping list, at £6.19, compared with £6.52 at Fiona's Foods and £9.06 at Peter's Provisions, but it would be even cheaper to shop around, buying lemonade and sausages at Fiona's Foods, crisps and chips at Gary's Groceries for a total of £5.96.
We thought the disadvantages of doing it this way would be that we would use more time and petrol.
Mollie added the following disadvantages to shopping at just one place:
- it might take different times to get to each of the shops.
- the shop might not have the type you want.
- the shop might be surrounded by more houses so be more popular and therefore have less stock.
Then Mrs Lydford's groups found some different ways not to go over their allotted £10.70 budget for the party food, by first working out which was the cheapest place to buy each item:
For the party, we found 8 ways of buying the food for under £10.70 by shopping around.
First we bought all the items in the cheapest places:
lemonade= £1.72 at Fiona's
sausages= £4.08 at peter's
chips= £2.40 at Gary's
crisps= £1.56 at Peter's
biscuits=84p at Fiona's
Total- £10.60
Next we substituted items which were close in price to make different totals, still under £10.70.
Change lemonade to Gary's - new total £10.64
Change lemonade to Peter's - new total £10.68
Change chips to Peter's - new total - £10.69
Change crisps to Peter's - new total - £10.63
Change biscuits to Peter's - new total - £10.65
Change biscuits to Gary's - new total - £10.70
Change lemonade to Gary's and crisps to Peter's - new total - £10.67.
Finally, Mollie answered the last part of our question:
Buy one get one free is the same as 50% off as you are getting double for the money in both situations. Hoever 50% off I think is better because you can decide whether to buy two lots where as with buy one get one free you might not use them within the sell by date.
If none of the supermarkets had a special promotion, I would shop at Fiona's, because she sells smaller packages but she charges less for them, so you can use them by the sell by date.
Teachers' Resources
Are You a Smart Shopper?
In my local town there are three supermarkets: Gary's Groceries, Fiona's Foods and Paul's Provisions.
This week they have each got a special deal on some products.
At Gary's Groceries, they are selling items at discount prices.
At Fiona's Foods, you can buy items which have a certain amount free.
At Paul's Provisions, there are some "buy one get one free" deals.
Have a look:
Gary's Groceries.
Fiona's Foods.
Paul's Provisions.
If you shopped at Gary's Groceries, how much would you actually pay for each item? So how much money have you saved on each?
Here is your shopping list:
- 2 bottles of lemonade (2litre size)
- 1 6 pack of crisps
- 24 sausages
- 1 bag of chips (1.8kg size)
If you bought all the items in one shop, where would be the cheapest?
If you could buy the items from different shops, how would you do it to spend the least amount of money?
Apart from the cost, can you think of any other advantages or disadvantages with buying these items at just one shop?
You have got £10.70 to spend on a party meal for you and nine friends. Here's your shopping list:
- 4 bottles of lemonade (2 litres)
- 4 packs of sausages (8 packs)
- 2 bags of chips (1.8kg)
- 2 bags of crisps (6 packs)
- 2 packs of biscuits (7 packs)
How can you do this so that you don't go over your budget?
How many different ways are there?
Which shop offers best value for money on each item?
What sorts of things do you need to take into account to answer this?
Is the "buy one get one free" deal at Paul's Provisions the same as if they had 50% off?
Why do this problem?
Possible approach
Younger children would enjoy having shops set up in the classroom and being involved in role play. Using empty packets and cartons, along with plastic money or tokens, would be a good way in for many pupils. Another excellent resource would be flyers or leaflets from local supermarkets advertising their offers. (We would have used these ourselves but would get in trouble for copyright reasons!)
Key questions
This investigation will stimulate a great deal of relevant discussion. Try to make the most of it! With only a small amount of examples, the children themselves should be able to suggest different scenarios which may affect where they would shop. This may lead into "what if?" type extensions, initially instigated by you but later by them too.
Possible extension
Some pupils might like to calculate the original size of each item at Fiona's Foods, before the percentage increase is applied. They could then compare the price of e.g. a single sausage at each supermarket, before and after the special offers are applied. (Children will need to be confident with decimals in order to do this!)
At a higher level, a more general approach can be taken, perhaps along the lines of consumer versus retailer benefits. You can open up the investigation further by splitting the class into groups and setting them off on a "shopping project" with certain aims and/or constraints.
Possible support
Some children will benefit from having the information in the tables broken down for them by a supporting adult, and focusing on one shop at a time might be helpful. Having coins available for children to use to add up the different prices might also be useful.