Question 218146
Velocity  =  Distance  / Time ,,,,,,or t=d/v
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outbound,,,,v=30/3 = 10 mph,,,,ok
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if  total  distance  is  60,,,and  avg  speed  is  to  be 15 mph, t= 60/15 = 4 hrs
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Since  we  already  used  3  hrs,,,only  one  hr  remains  to  go  30  miles,,,and  v=d/t = 30/1 =30mph
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Of  course,  neglecting  any  time  spent  at  Salisbury  Beach
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