document.write( "Question 628134: mike and dave are roommates. one day mike wakes up and goes for his morning run. He runs 8 miles per hour. an hour later, dave leaves ro his morning bike ride traveling the same route as mike. Dave bikes 20 miles per hour. How log will mike have been running when dave catches him? \n" ); document.write( "

Algebra.Com's Answer #395416 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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Mike runs 8 miles per hour. An hour later, Dave leaves for his morning bike
\n" ); document.write( " ride traveling the same route as mike.
\n" ); document.write( " Dave bikes 20 miles per hour.
\n" ); document.write( " How long will mike have been running when Dave catches him?
\n" ); document.write( ":
\n" ); document.write( "Let t = Mike's running time
\n" ); document.write( "then
\n" ); document.write( "(t-1) = Dave's travel time (left an hr after Mike)
\n" ); document.write( ":
\n" ); document.write( "When Dave catches Mike, they will have traveled the same distance.
\n" ); document.write( "Write a distance equation: dist = speed * time
\n" ); document.write( ":
\n" ); document.write( "20(t-1) = 8t
\n" ); document.write( "20t - 20 = 8t
\n" ); document.write( "20t - 8t = 20
\n" ); document.write( "12t = 20
\n" ); document.write( "t = 20/12
\n" ); document.write( "t = 1 $\"2%2F3\"$ hrs which would be 1 hr 40 min, Mike's running time.
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check this by finding the dist each traveled, should be equal
\n" ); document.write( "Mike: 1.67 * 8 = 13.33 miles
\n" ); document.write( "Dave: .67 * 20 = 13.33 miles \n" ); document.write( "

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