a child is 40 inches tall, which places her at the 90th percentile of all children of similar age. the heights for children of this age form an approximately normal distribution with a mean of 38 inches. based on this information, what is the standard deviation of the heights of all children of this age?

Respuesta :

Since the mean height of all children this age is 38 inches, the z-score is 1.282, and the child's height is 40 inches, the standard deviation of all children's heights will be 1561.

What is standard deviation?

The standard deviation is a statistic that expresses how much variance or dispersion there is in a group of numbers. While a high standard deviation suggests that the values are dispersed throughout a larger range, a low standard deviation suggests that the values tend to be near to the established mean. The term "standard deviation" (or "") refers to a measurement of the data's dispersion from the mean. A low standard deviation indicates that the data are grouped around the mean, whereas a high standard deviation shows that the data are more dispersed.

Here,

The z-score which separates the top 10% of a normally distributed

population is 1.282.

Since z = (x-u)/sigma

1.282 = (40-38)/sigma

sigma = 2/1.282

sigma = 1/0.641 = 1561

The standard deviation of the heights of all children of this age will be 1561 as mean is 38 inch and z-score is 1.282 as well as the height of child is 40 inch.

To know more about standard deviation,

https://brainly.com/question/13905583

#SPJ4