Answer:
The cut-off dollar amount is $328.
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 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. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Mean cost of $328, standard deviation of $82.
This means that
If you want to be in the bottom 50%, what will be the cut-off dollar amount?
The 50th percentile, which is X when Z has a pvalue of 0.5. So X when Z = 0.
The cut-off dollar amount is $328.