If Dorie devotes the same number of hours to studying for these three classes each week, what is the total number of hours Kathleen will study over a three week period?
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Answer:
The answer is 17.2 hours
Step-by-step explanation: Because first you add all hours together (which is 86/15) then multiple it by 3 (week) which is 86/5 = 17.2 hours