P - 396 = t <== ur equation
Answer:
P(X < 80) = 0.89435.
Step-by-step explanation:
When the distribution is normal, we use 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.
In this question, we have that:

P(X < 80)
This is the pvalue of Z when X = 80. So



has a pvalue of 0.89435.
So
P(X < 80) = 0.89435.
Any rational number will satisfy the situation.
Answer:
C. One can be 95% confident that the true proportion of all students receiving financial aid is between 0.52 and 0.66
Step-by-step explanation:
Given that the confidence interval is a term that defines a range of values with the probability to contain a population value that has an actual degree of confidence.
This is represented in a situation where population means falls in between upper and lower intervals.
Hence, in this case, the correct interpretation is option C: One can be 95% confident that the true proportion of all students receiving financial aid is between 0.52 and 0.66