SOLUTION: determine the approximate probability that the value of the standard normal random variable will be greater than -1 and less than +2.

Question 1169469: determine the approximate probability that the value of the standard normal random variable will be greater than -1 and less than +2.
Answer by Theo(13342) (Show Source): You can put this solution on YOUR website!
here's an approximate graph you can use.

the approximate percentage is 34.13 + 34.13 + 13.59 = 85.85%.

i used a normal distribution calculator to confirm this is reasonable.

the calculator says 81.86%.

that's pretty close, so the approximate answer is reasonable.

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