The normal probability calculator gives us the area underneath a specified normal curve between two points. In order to find the probability that a normal variable lies between two points input the values of the lower bound and upper bound into the calculator.
If you want to calculate the cumulative probability (probability less than a certain value), then enter the value of the variable for the upper bound and put the value of the lower bound to be equal to -3\sigma.
Area (probability) = 0.7263
