abstract:A standard normal table, also called the unit normal table or Z table, is a mathematical table for the values of Φ, which are the values of the cumulative distribution function of the normal distribution. It is used to find the probability that a statistic is observed below, above, or between values on the standard normal distribution, and by extension, any normal distribution.
The table of standard normaldistribution was handled correctly by use of Raphsonnumericalintegral, by this way, the optimumdesign was connected withreliability design organically.