Question 1104493
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Please have the courtesy to check your statement of the problem before submitting it.  The tutors here don't want to have to spend time trying to figure out what you really meant.<br>
Obviously John travels 35 MILES farther than Mary -- not 35 minutes farther.<br>
So Mary drives distance x miles at 40mph, and John drives (x+35) miles at 85mph; and the time for John's trip is 15 minutes (1/4 hour) shorter than the time for Mary's:<br>
{{{(x+35)/85 = x/40-1/4}}}
{{{(x+35)/85 = (x-10)/40}}}
{{{85(x-10) = 40(x+35)}}}
{{{85x-850 = 40x+1400}}}
{{{45x = 2250}}}
{{{x = 50}}}<br>
John drives 50+35=85 miles at 85 mph; his trip takes 85/85 = 1 hour.<br>
Mary drives 50 miles at 40 mph;her trip takes 5/4 hours = 1 hour 15 minutes.