At the beginning of today's class students reviewed the work they did in yesterday's class with histograms as well as reviewing the rules that they created for themselves. The first activity was to draw a histogram by hand using data taken from the class about when students had birthdays. Each group was allowed to choose their own intervals for each histogram, so they could see that many different histograms could be created from the same data. Then students made their own histograms using data collected from the internet. Students made graphs of movies sorted by gross profit, motor vehicle registrations by state, as well as high and low temperatures by state. Students then printed out their graphs and were asked to write down one thing that they could conclude about the data from looking at their histogram.
After their break students began the new topic of probability. They looked at the forest fire activity on Interactivate, where probability is used to model the spread of forest fires. Students looked at a probability of zero for a tree next to an already burning tree catching fire and saw that none of the forest would burn down in that case. They also saw that the entire forest would burn down when that probability was one hundred percent. After plotting those two points on a graph students were asked to predict what percent of the forest would burn down when the probability was fifty percent. They agreed that about fifty percent of the forest would burn down, but after trying it in the model they found that a wide range of values were obtained. Finally, a new graph was made where each group found the percent of the forest that burned for a different probability and it was found that it was not a linear relationship, but rather an s-shaped curve.