1. The variable X is normally distributed. The mean is 15.2 and the standard deviation is 0.9 find P(x>16.1)
A. 0.1550
B. 0.8413
C. 0.1587
D. 0.1357
2. Score on a stats test are normally distributed with a mean of 32.7 and a standard deviation of 8.2. Find the 41st percentile
A. 30.8
B 27.9
C. 34.6
D. 37.5
Please help thank you so much
A. 0.1550
B. 0.8413
C. 0.1587
D. 0.1357
2. Score on a stats test are normally distributed with a mean of 32.7 and a standard deviation of 8.2. Find the 41st percentile
A. 30.8
B 27.9
C. 34.6
D. 37.5
Please help thank you so much
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1. P(x > 16.1) = P(z > (16.1 - 15.2)/0.9) = P(z > 1) = 1 - P(z < 1) = 1 - 0.8413 = 0.1587
2. need the value x, such that probability of being less than or equal to this number is about 0.41
this corresponds to z = -0.23 --> x = (-0.23)(8.2) + 32.7 = 30.8
2. need the value x, such that probability of being less than or equal to this number is about 0.41
this corresponds to z = -0.23 --> x = (-0.23)(8.2) + 32.7 = 30.8