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? asked in Science & MathematicsMathematics · 1 decade ago

what is the probability a random number will lie 1 standard deviation to the right of the mean?

is it .68? just one standard deviation or is it .34 because you are asking only to the right? Also, what is the probability if you are trying to find the probability of one mean and one std div.? is it the same?

1 Answer

  • 1 decade ago
    Favorite Answer

    The probability that a normally distributed random number will fall exactly one standard deviation to the right of the mean is zero.

    If you mean, what is the probability that the random number is to the right of a point one standard deviation from the mean on the right side, it is .5- 0.682689492/2. You are looking at the right half of the bell curve only. You have .3413 within one standard deviation to the right. The tail on the right side is .1587.

    Drawing a bell curve will help you visualize this.

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