Since the normal distribution curve is symmetric about the mean, this means that the z-score with an area of. It told me that the z-score that had an area to the left of it equal to. The calculator i used was in the TI-84 Plus. You can find this area using the z-score tables, or you can find it using a z-score calculator. This says that 19% of the area under the normal distribution curve is to the left of z1. You have 19% of the area under the normal distribution curve to the left of the middle 62% and you have 19% of the area under the normal distribution curve to the right of the middle 62%. That makes each of those areas equal to 38% / 2 = 19%. Half of this is in the lower end of the normal distribution and half of this is in the upper end of the normal distribution. The area outside the middle of the distribution is therefore equal to 100% - 62% = 38%
The total area of the normal distribution is equal to 100%. Since the middle distribution is equal to 62%, then you get: The middle distribution is therefore equal to z2 minus z1. Let z1 = the low end of the middle distribution. Let z2 = the high end of the middle distribution. You can put this solution on YOUR website!
