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consider a normally random variable . for a z-score equal to 1, what is the value of this realization of the random variable x (i.e., ?

User Wolfetto
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Final answer:

The value of a random variable X for a z-score of 1 is found using the formula X = μ + (z)(σ), where μ is the mean and σ is the standard deviation of the normal distribution X. For example, if X~N(5, 6), then X equals 11 when the z-score is 1.

Step-by-step explanation:

The student has posed a question regarding the z-score and its application to normally distributed variables. Specifically, the student is asking what the value of the realization of a random variable X is when the z-score is equal to 1.

To determine this, we use the formula for finding the value of X from its z-score:

X = μ + (z)(σ)

Where μ is the mean of the normal distribution X and σ is the standard deviation. If X~N(μ, σ), and z is the z-score for a value x from this distribution, then the z-score tells how many standard deviations x is above (if positive) or below (if negative) the mean μ. For z = 1, the value of x would be one standard deviation above the mean, which can be calculated using the provided formula. As an example, if the distribution is X~N(5, 6), then:

X = 5 + (1)(6) = 11

So, in this case, x equals 11 when the z-score is 1.

User Mara Morton
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