scores on the gre (graduate record examination) are normally distributed with a mean of 535 and a standard…
scores on the gre (graduate record examination) are normally distributed with a mean of 535 and a standard deviation of 122. use the 68 - 95 - 99.7 rule to find the percentage of people taking the test who score between 291 and 779.\nthe percentage of people taking the test who score between 291 and 779 is %.
Answer
Explanation:
Step1: Calculate number of standard - deviations from the mean
First, find how many standard - deviations 291 and 779 are from the mean of 535. For (x = 291), (z_1=\frac{291 - 535}{122}=\frac{- 244}{122}=- 2) For (x = 779), (z_2=\frac{779 - 535}{122}=\frac{244}{122}=2)
Step2: Apply the 68 - 95 - 99.7 Rule
The 68 - 95 - 99.7 Rule states that for a normal distribution: Approximately 95% of the data lies within (z=-2) and (z = 2) standard - deviations of the mean.
Answer:
95