<PRE><B>Question 840039</B>
 Wilma drove at an average speed of 45 mi/h from her home in City A to visit her sister in City B.
 She stayed in City B 25 hours, and on the trip back averaged 50 mi/h.
 She returned home 45 hours after leaving.\
 How many miles is City A from City B?
:
From the given information, we know the travel time there and back = 20 hrs
:
let d = the one-way distance
write a time equation; time = dist/speed
:
AB time + BA time = 20 hrs
{{{d/45}}} + {{{d/50}}} = 20
Multiply by 450 to clear the denominators
10d + 9d = 9000
19d = 9000
d = 9000/19
d = 473.7 mi is the one-way distance
:
:
Check by finding the time each way:
473.7/45 = 10.5 hrs
473.7/50 =  9.5 hrs
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total time: 20 hrs</PRE>