A local bank has determined that the daily balances of the checking accounts of its customers are normally distributed with an average of $280 and a standard deviation of $20.
a. What percentage of its customers has daily balances of more than $275?
b. What percentage of its customers has daily balances less than $243?
c. What percentage of its customers' balances is between $241 and $301.60?
It's important that you show, with your narrative, how you arrived at your answers for this forum. Please be sure to do that by mentioning the source of your information and citing it. We are not merely looking for answers a, b, and c. You must explain the process through strong narrative.
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