SOLUTION: 1. The annual per capita consumption of ice cream​ (in pounds) in the United States can be approximated by a normal distribution with mean of 14 lbs and a standard deviation

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Question 1072204: 1. The annual per capita consumption of ice cream​ (in pounds) in the United States can be approximated by a normal distribution with mean of 14 lbs and a standard deviation of 2.1 lbs.

a. What percent of the population consumes at most 10 lbs​ yearly?
b. Jack estimates that​ 24% of the population eats more ice cream than he does. Find how much ice cream he eats per year.
c. Between what two values does the middle​ 80% of the consumption​ lie?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
at most 10 is z < (10-14)/2.1 or -1.905
probability z < -1.905 is 0.0284 or 2.84%
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z value for the 76th percentile is 0.705
0.705=(x-14)/2.1
1.4805-x-14
x=15.48 lb.
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That is 10% on each side which corresponds to a z value of +/-1.28
1.28=(x-14)/2.1
x-14=2.69
x=16.69 lb top end
x=11.31 pounds bottom end
(11.31 lb, 16.69 lb) is the interval.