We take that great old problem of the inventor of chess and the ruler of India and use it to see how powers of 2 grow in size. We start out with a chessboard and look at doubling each successive number. Then we seek a method of representing this doubling in a formula and introduce exponents and powers of 2. We ask you what kind of rule would you suggest that would keep your head and please the ruler?
Category: Ratio
Rate of Growth
We look at world population over the past 60+ years and ask whether the earth’s population is growing faster or slower today. Is it out of control and something we should all worry about or are we getting it under control? This is another problem directly related to climate change and one that students can argue with each other about. We use this opportunity to ask students about which kind of graph or chart would best convey the issue to other people. The type of graph or chart to be used to convey data is of great importance in business and industry today and one that requires students to creatively ask What if… about.
CO2 Growth
Spreadsheets offer us a nearly unlimited ability to develop and learn from case studies using real world data. We will focus mainly on climate change which is an area rich in possibilities and of great interest to students. In this case study we look at the production of carbon dioxide per person in the United States over the past 200 years. We take this opportunity to introduce students to the difference between quantity and growth, between the amount of CO2 produced and the year-to-year growth in production. We challenge students to consider whether this growth is an increasing problem.
Normal Distribution
Most museums with math exhibits have a Pascal’s triangle made up of pegs with balls falling down between them and bouncing off of them. One of the things they want to show is probability and the Normal or Bell curve produced by these balls as they fall down most of us are familiar with. This is the curve produced if we flip a honest coin a large number of times and ask what are the chances of getting all heads, of all heads but one and one tail, of getting all but 2 heads etc. We ask what does a Normal distribution look like and why does this extremely simple pattern produce it?
Pascal’s Triangle
Another famous pattern, Pascal’s triangle, is easy to construct and explore on spreadsheets. Create a formula for any cell that adds the two cells in a row (horizontal) above it. This pattern is like Fibonacci’s in that both are the addition of two cells, but Pascal’s is spatially different and produces extraordinary results. Pascal’’ triangle is related to an amazing variety of mathematics, things like Fibonacci’s sequences, the triangular numbers, the powers of 2, the binomial theorem, the Bell curve, and more, so much more. We invite you to explore!