Question: The following cumulative relative frequency distribution summarizes data obtained in a study of the ending overages (in dollars) for the cash register balance at a business:
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a. Determine the proportion of the days in which there were no shortages.
b. Determine the proportion of the days the cash register was less than $20 off.
c. Determine the proportion of the days the cash register was less than $40 over or at most $20 short.