Using the normal distribution, the areas to the left are given as follows:
a) 0.7910.
b) 0.6664.
c) 0.3707.
d) 0.8508.
Normal Probability Distribution
The z-score of a measure X of a normally distributed variable with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex] is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
- The z-score measures how many standard deviations the measure is above or below the mean.
- Looking at the z-score table, the p-value associated with this z-score is found, which is the percentile of X, and is also the area to the left of Z.
Hence:
- The area to the left of Z = 0.81 is of 0.7910.
- The area to the left of Z = 0.43 is of 0.6664.
- The area to the left of Z = -0.33 is of 0.3707.
- The area to the left of Z = 1.04 is of 0.8508.
More can be learned about the normal distribution at https://brainly.com/question/4079902
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