If ? is a random variable that follows a normal distribution with a mean of 20 and standard deviation 3.2, what value of ? represents the 50th percentile?
Solution :
mean = = 20
standard deviation = = 3.2
Using standard normal table,
P(Z < z) = 50% = 0.50
P(Z < 0) = 0.50
z = 0
Using z-score formula,
Y= z * +
Y = 0 * 3.2 + 20 = 20
50th percentile =20
If ? is a random variable that follows a normal distribution with a mean of 20...
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