Assume a data set is normally distributed with mean 129 and standard deviation 35. If the data set contains 350 data values, approximately how many of the data values will fall within the range 59 to 199?
A) 88
B) 239
C) 123
D) 334

Question

Quizplus · Accepted Answer

Approximately 95% of data in a normal distribution falls within two standard deviations from the mean. Here, 59 to 199 is two standard deviations from the mean (129 ± 2*35). Therefore, 95% of 350 data values is approximately 334.

Assume a Data Set Is Normally Distributed with Mean 129