combining binomial & normal distribution

Apr 2009
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0
if 4 items are chosen at random, what is the probability that their average length is greater than 35cm.
mean = 35.05cm
std dev = 0.2

i know that the probability of 1 item greater than 35cm is 0.5987 but unsure how to include 4 items and find mean? maybe binomial?
 

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if 4 items are chosen at random, what is the probability that their average length is greater than 35cm.
mean = 35.05cm
std dev = 0.2

i know that the probability of 1 item greater than 35cm is 0.5987 but unsure how to include 4 items and find mean? maybe binomial?
Read this: Sample Means
 
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