It's 12x. you just combine both numbers
2z +7 = -5
2z = -5 -7
2z = -12
z= -12 /2
z= -6
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

⇒ 
⇒ 
⇒ 
Hence we can conclude that the value of z-score for a score that is three standard deviations above the mean is 3.
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Answer:
Saturday=403 tickets
Step-by-step explanation:
1246-314-529=403