Question 1075099
mean is 1 kg.
standard deviation is .2 kg.


you want probability that the chicken weighs less than 1.5 kg.


z-score = (x-m)/s


x = 1.5 kg
m = 1 kg
s = .2 kg.


formula becomes z = (1.5 - 1) / .2


result is z = 2.5


probability of a z-score less than 2.5 is equal to .9938


in other words, the vast majority of the chickens will weight less than 1.5 kg if the mean is 1.0 kg and the standard deviation is .2 kg.


here's the results using z-scores and using raw scores.


the results are the same, as they should be.


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