The Saskatoon Credit Union selected a sample of 40 student chequing accounts. Below are their end-of-the- month balances, in dollars: $404 74 234 149 279 215 123 55 43 321 87 234 68 489 57 185 141 758 72 863 703 125 350 440 37 252 27 521 302 127 968 712 503 489 327 608 358 425 303 203
a. Tally the data into a frequency distribution using $100 as a class interval and $0 as the starting point.
b. Draw a cumulative frequency polygon.
c. The bank considers any student with an ending balance of $400 or more a "preferred customer." Estimate the percentage of preferred customers.
d. The bank is also considering a service charge to the lowest 10% of the ending balances. What would you recommend as the cut-off point between those who have to pay a service charge and those who do not?