<PRE><B>Question 414462</B>
Given: mean is $25 and standard deviation is $8. Find dollar amount such that 80% of all customers spend at least this amount.
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Find the z-value with a left tail of 20%.
invNorm(0.2) = -0.8416
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Find the corresponding x-value:
x = zs + u
x = -0.8416*8 + 25 = $18.27
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Cheers,
stan H.</PRE>