The rule is often called Chebyshev's theorem, about the range of standard deviations around the mean, in statistics. The inequality has great utility because it can be applied to completely arbitrary distributions (unknown except for mean and variance). For example, it can be used to prove the weak law of large numbers. In practical usage, in contrast to the 68-95-99.7% rule, which applies to normal distributions, under Chebyshev's inequality a minimum of just 75% of values must lie within two standard deviations of the mean and 89% within three standard deviations.
City of Page. Welcome to City of Page, Arizona. Page is a small town in northern Arizona located on the southern shores of magnificent Lake Powell. Our friendly community offers visitors outstanding recreation and a wide variety of lodging and services.
Page Arizona. Gateway To Lake Powell. Located in Northern Arizona, near the Utah border, Page AZ is the Gateway to Lake Powell and the Glen Canyon National Recreation Area. Created in in the 1960s as the base camp for construction workers on Glen Canyon Dam, Page has become the center hub of Northern Arizona attractions and things to do and see for visitors, tourists, and vacationers.