It is $6 more now than before...maybe you were looking for percent increase?
%change=100(final-initial)/initial
%change=100(10-4)/4=150% increase
You need to multiply the two numbers. Or you can use long addition.
The value of z-score for a score that is three standard deviations above the mean is 3.
In this question,
A z-score measures exactly how many standard deviations a data point is above or below the mean. It allows us to calculate the probability of a score occurring within our normal distribution and enables us to compare two scores that are from different normal distributions.
Let x be the score
let μ be the mean and
let σ be the standard deviations
Now, x = μ + 3σ
The formula of z-score is

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Hence we can conclude that the value of z-score for a score that is three standard deviations above the mean is 3.
Learn more about z-score here
brainly.com/question/13448290
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