Answer:
a) The mean is 
b) The standard deviation is 
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
The probability a student selected at random takes at least 55.50 minutes to complete the examination equals 0.6915.
This means that when X = 55.5, Z has a pvalue of 1 - 0.6915 = 0.3085. This means that when 
So




The probability a student selected at random takes no more than 71.52 minutes to complete the examination equals 0.8997.
This means that when X = 71.52, Z has a pvalue of 0.8997. This means that when 
So




Since we also have that 





Question
The mean is 
The standard deviation is 
Answer:
um yes it can it can if you look at a ruler in try it it would be the same
Step-by-step explanation:
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Answer: g(x) = 3/2 x + 9
Step-by-step explanation:
h(x) = -2/3 x - 1
perpendicular lines always have the opposite sign, reciprocal slope
so, the slope of the perpendicular line would be: m = 3/2
y = mx + b
y = 3/2 x + b
plug in (-4, 3) to find b
3 = 3/2 (-4) + b
3 = -6 + b
b = 9
y = 3/2 x + 9
g(x) = 3/2 x + 9
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