SOLUTION: Americans receive an average of 22 Christmas cards each year. Suppose the number of Christmas cards is normally distributed with a standard deviation of 6. Let X be the number of C

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Question 1178852: Americans receive an average of 22 Christmas cards each year. Suppose the number of Christmas cards is normally distributed with a standard deviation of 6. Let X be the number of Christmas cards received by a randomly selected American. Round all answers to 4 decimal places where possible.
a. What is the distribution of X? X ~ N(
22
,
6
)
b. If an American is randomly chosen, find the probability that this American will receive no more than 21 Christmas cards this year.
.433816

c. If an American is randomly chosen, find the probability that this American will receive between 24 and 29 Christmas cards this year.
.2478

d. 78% of all Americans receive at most how many Christmas cards? (Please enter a whole number)

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!

Hi
a)  Normal distribution:  µ = 22 and σ = 6
b) .4338
c) .2478
d) 78% of all Americans receive at most how many Christmas cards? invNOrm(.78) = .7722
z+=blue+%28x+-+mu%29%2Fblue%28sigma%29 OR z%2A%28blue%28sigma%29%29+%2B+mu=blue+%28x%29
.7722(6) + 22 =x = 26.6332 0r receive at most 26 Christmas cards 
Wish You the Best in your Studies.