Calculating the Cost of a Simple Summer Wardrobe

After our lesson Maths Fun - Exploring Real Data with Excel students were eager to have a play with Excel themselves. We were reading Onion Tears by Diana Kidd, and had read about how the main character Nam-Huong had arrived by boat with only the clothes she was wearing. We undertook an investigation to find out how much it would cost to get a simple summer wardrobe for Nam-Huong.

We began by considering the items of clothing that Nam-Huong would need and made a list on the board. After much discussion, and a last minute addition of a dress, we were ready to move on!

I put my students into small groups and each was given an iPad and access to a desktop computer (because we didn't have a spreadsheet app on the iPads). They were also allocated a shop to use for their pricing. We used Target, Kmart, Big W, David Jones and Myer. Students found the online catalogue for their store and searched through to find the price of the required items. They then added these to their spreadsheet.

Once they had all their totals, they used the formula =PRODUCT(B3:C3) and filled down the column. Once they had all totals they used the formula =SUM(D3:D12) to calculate the grand total.

Once everyone had finished, groups shared their results with the class and we were able to compare the grand total of each store. As always, when using real data the "answer" is never straightforward and this led to some great discussion. For example, one store didn't have all the required items in the catalogue and even when they searched the store online they were unable to find the price for a pair of socks. Another group had trouble finding a hat, and ended up settling for a Santa's elf hat. And one group was paying $25 per pair of underpants - severely impacting on their total cost. When asked, they said quite innocently, "They were frilly." I'm sure they were exactly what Nam-Huong needed when she arrived in Australia...along with her Santa elf hat! I'm not going to tell you who came in cheapest - you'll have to investigate that yourself. ;)

Further discussion arose about the need to monitor your online presence as a business to succeed in the market place. We talked about how many people now shop online, making it essential to have a website that helps people to find and purchase what they need. From our experiences there are some stores better positioned in this marketplace.

We had a lot of fun with this maths investigation and students rose to the challenge and learnt new computer skills. The following week we set a homework task where students could collect and represent their own data. One of my students decided to calculate cost and labour for a new pergola using Excel!