The Normal Distribution

Intro —
1. Properties: continued
  1. The distribution is symmetric about the mean.
  2. The mean, median and mode are all equal.
  3. The graph is an idealized* representation of
    the data's histogram... an illustrative explanation?
    (*i.e., it has infinite detail or resolution)
  4. 68.26% of the graph's area lies in the interval
    between µ - σ and µ + σ, 95.44% of the area
    lies in the interval between µ - 2σ and µ + 2σ,
    and 99.74% of the area lies in the interval
    between µ - 3σ and µ + 3σ...
2. Key Principle:
  The percentage of the data in any interval equals
  the percentage of the histogram's (or the normal curve's) total area contained in the portion of the graph which lies over the interval (a < x < b).