Suppose X is normally distributed with mean 20 and standard deviation 4, find the value x0 such that P(X ≥ x0) = 0.975.
1 answer:
Answer:
12.16
Step-by-step explanation:
From your question, we have the following information
Mean = u = 20
Standard deviation sd = 4
P(X>Xo) = 0.975
1-0.975 = 0.025
P(z<Xo-20/4) = 0.025
Xo-20/4 = -1.96
We cross multiply
Xo - 20 = -1.96 x 4
Xo - 20 = -7.84
Xo = -7.84+30
Xo = 12.16
12.16 is the value of Xo and therefore the answer to this question.
Thank you!
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