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.
Warnings: 1  This stains pretty much everything from clothing to skin to white counter tops. put down some newspaper! 2  The dryer and more brittle hair will keep in the color the longest. 3  Sometimes, the red Kool-Aid can be permanent (from what Iâve heard online)  Can last longer than two weeks (as did mine)