It is a common rule of thumb in business; e.g., "80% of your sales come from 20% of your clients." Mathematically, the 80/20 rule is roughly followed by a power law distribution (also known as a Pareto distribution) for a particular set of parameters, and many natural phenomena have been shown empirically to exhibit such a distribution.
He then carried out surveys on a variety of other countries and found to his surprise that a similar distribution applied.
Once students begin to grasp "relative" dating, they can extend their knowledge of geologic time by exploring radiometric dating and developing a timeline of Earth's history.
The Platinum Rule far predates the How I Met Your Mother episode of the same name.
Instead of insisting that she shut up and let me open her doors, I abide by the Platinum Rule, and I let her open her own doors when she wants to. Juran suggested the principle and named it after Italian economist Vilfredo Pareto, who noted the 80/20 connection while at the University of Lausanne in 1896, as published in his first paper, "Cours d'économie politique".Essentially, Pareto showed that approximately 80% of the land in Italy was owned by 20% of the population; Pareto developed the principle by observing that about 20% of the peapods in his garden contained 80% of the peas.However, "relative" dating or time can be an easy concept for students to learn.In this activity, students begin a sequencing activity with familiar items letters written on cards.It is similar to the Golden Rule, but more considerate.