Question 1176546
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A tour bus normally leaves for its destination at 5:00 p.m. for a 300 mile trip. This week however, the bus leaves at 6:00 p.m. 
To arrive on time, the driver drives 10 miles per hour faster than usual. What is the bus` usual speed?
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Let x be its regular speed, in miles per hour.

Then the increased speed is (x+10) mph.


The regular travel time is  {{{300/x}}}  hours.

The travel time with increased speed is  {{{300/(x+10)}}}  hours.


The difference of traveled time is (from the context) 1 hour


    {{{300/x}}} - {{{300/(x+10)}}} = 1  hour.


It is your time equation to find x.


You can guess the solution MENTALLY just from this point: it is  50 mph.     <U>ANSWER</U>


Indeed,  {{{300/50}}} - {{{300/(50+10)}}} = {{{300/50}}} - {{{300/60}}} = 6 - 5 = 1 hour.


Or, alternatively, you may reduce equation (*) to quadratic equation and solve it formally.
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At this point, the solution is completed.