Answer:
z = 1.77.
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 z-score 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, which is also the area of the normal curve to the left of Z. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Find z such that 3.8% of the standard normal curve lies to the left of z
Thus, z with a z-score of 0.038. Looking at the z-table, this is z = 1.77.