Normal Distribution and z-scores. mean: the average obtained by dividing the sum of the data by the number of data in the set. Given a set of data, {x 1, x 2, x 3, ..., x n }, you can find the mean, , using the following formula: standard deviation: the extent to which data differs from the mean.
Quick Answer. Kool-Aid hair dye hair dye can last for eight to 12 weeks. The intensity of the color depends on several factors such as the natural hair color, the amount of time the hair is soaked with the dye, the amount of dye used and the dyeing method used. Continue Reading.
How long does Indigo hair dye last. Indigo is a permanent hair dye. However, different kinds of hair can react differently to it. For example, blonde or grey hair need several Indigo application before you get your desired blackish color. Dark hair, however, will immediately become deep black.