Question 111994
 A bus leaves a station at 1pm, traveling west at an average rate of 44m/h. One hour later a second bus leaves the same station at, traveling east at a rate of 48m/h. At what time will the two buses be 274 miles apart?
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The best way to do this is just write an equation that adds the two distances to equal 274 mi:
;
Let t = travel time (in hrs) of the 1st bus to be 274 mi from the 2nd bus
Then
(t-1) = travel time of the 2nd bus to reach that 274 mi point
:
Distance = speed * time
:
2nd bus dist + 1st bus dist = 274
48(t-1) + 44t = 274
48t - 48 + 44t = 274
48t + 44t = 274 + 48
92t = 322
t = 322/92
t = 3.5 hrs
:
3.5 hrs after 1 pm = 4:30 the time they're 274 mi apart
:
:
WE can check this, the 2nd bus is traveling for only 2.5 hrs
48*2.5 = 120 mi from the starting point at 4:30 (leaves at 2pm)
44*3.5 = 154 mi from the starting point at 4:30 (left at 1 pm)
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total mi:274 mi
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Did this make sense to you?