Today we worked on Yellow Starbursts, a 3 Act Math lesson by Dan Meyer. You can find the activity here.
We began by watching the following video.
When it was over, I asked the students to write down one question they had about the video. We discussed the questions as a class. After writing down all the questions I told them we would be trying to figure out how many of the packets had 2 yellow starbursts and how many would have 1 yellow starbursts.
Then I asked the students what else they needed to know to find the solution. They said they would need to know if yellow starbursts had the same frequency as the other colors. I then showed them the picture with the starburst frequencies. Students then worked in groups to complete the problem.
They had some really great approaches. Most groups used the probability of compound events, but they had different ways of going about it. Finding the number of packs with 1 yellow was the hardest. You can see some of their approaches to this below.
The group below made a very common mistake. To find the number of packs with one yellow, they took the probability of yellow (28%) and multiplied this by the total number of starburst packs (287). This led to a really nice discussion of why this doesn’t work. We also talked about what we could salvage from their work and what we needed to change to correct the issue. They had correctly found the number of double yellow packs to be 23. The 80 packs they found represented 160 yellow single starbursts. We took 46 away from that because 46 yellow starbursts were already taken in the double packs. This left us with 114 yellow starbursts which must mean there are 114 packs with 1 yellow since we can’t put any of them together because we already did all the double yellow packs. I thought this was a really cool approach to the problem.
These groups did a really nice job presenting all of their work.