Respuesta :
range of the variable defines an area under the curve corresponding to a probability of approximately 68% is from 10 to 20
Given :
for a normal distribution curve with the mean of 15 and a standard deviation of 5.
Lets look at the graph of normal distribution
mean is 15 that is in the middle
First standard deviation is 15+5=20
second is 20+5=25
third is 25+5=30
the graph is attached below.
In this middle two areas shows 34% and 34%
34+34=68%
So range of the variable defines an area under the curve corresponding to a probability of approximately 68% is from 10 to 20
Learn more : brainly.com/question/14644201

