SOLUTION: Good morning!! Please I need help to find the specified normal distribution Ice Cream � The annual per capita consumption of ice cream (in pounds) in the United States can be a

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Question 709414: Good morning!!
Please I need help to find the specified normal distribution
Ice Cream � The annual per capita consumption of ice cream (in pounds) in the United States can be approximated by a normal distribution, as shown in the graph.
(a) What is the smallest annual per capita consumption of ice cream that can be in the top 25% of consumption?
(b) What is the largest annual per capita consumption of ice cream that can be in the bottom 15% of consumption?
Annual U.S. per Capita Ice Cream Consumption
� = 16.5 lb
σ = 2.5
--|-----|------|------|------|------|�
8 10 12 14 16 18 20 22 24 26
Consumption (in Pounds)
I used the formula z=x-�/ but I can�t find the right solution.

Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
The annual per capita consumption of ice cream (in pounds) in the United States can be approximated by a normal distribution, as shown in the graph.
(a) What is the smallest annual per capita consumption of ice cream that can be in the top 25% of consumption?
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Find the z-value with a left tail of 75%: invNorm(0.75) = 0.6745
Find the corresponding pounds value using x = z*s+u
x = 0.6745*2.5+16.5 = 18.19 lb.
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(b) What is the largest annual per capita consumption of ice cream that can be in the bottom 15% of consumption?
invNorm(0.15) = -1.0364
x = -1.0364*2.5+16.5 = 13.91 lbs
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Cheers,
Stan H.
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Annual U.S. per Capita Ice Cream Consumption
� = 16.5 lb
σ = 2.5
--|-----|------|------|------|------|�
8 10 12 14 16 18 20 22 24 26