Suppose X is normally distributed with mean 4 and standard deviation 4. Find the probability that 2X exceeds 7.
Group of answer choices
.5497
Suppose a random sample of 25 measurements is taken from a population with mean 17 and variance 100. The variance of the sample mean is
Group of answer choices
2
0.68
4
17
100
.301
.4012
.4555
.5988
Solution :
Given that ,
mean = = 4
standard deviation = = 4
P(x > 7) = 1 - P(x < 7)
= 1 - P[(x - ) / < (7 - 4) / 4)
= 1 - P(z < 0.75)
= 1 - 0.7734
= 0.2266
Probability = 0.2266
mean = = 17
standard deviation = = 10
n = 25
= 17
= / n = 10 / 25 = 2
Suppose X is normally distributed with mean 4 and standard deviation 4. Find the probability that...
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