Question 455421
A list of numbers have mean 7 and standard deviation 2.5. If x is a number in the list that is 2 standard deviation above mean then what is the value of x ?
please explain the procedure
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Since z = (x-u)/s, x = zs+u
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You have 
u = 7
s = 2.5
z = 2
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So, x = 2*2.5+7
x = 12
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Cheers,
Stan H.