SOLUTION: Michael averaged running a certain distance 1 mph faster than David ran the same distance. If it took Michael 36 minutes to run the distance and it took David 4 minutes longer to r

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Question 1048956: Michael averaged running a certain distance 1 mph faster than David ran the same distance. If it took Michael 36 minutes to run the distance and it took David 4 minutes longer to run the same distance, how far did the boys run?
I don't even know how to begin to set up this problem into an equation, other than distance=rateXtime.

Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39625) About Me  (Show Source):
You can put this solution on YOUR website!
According to RT=D for the basic constant travel rates rule, here is an the tabulation for the problem description.

Speed unit of MILES per HOUR, time unit as HOURS, and distance as MILES:

               SPEED             TIME               DISTANCE
Michael        r+1               36/60               d
David           r                4/60+36/60          d

If you understand that, then simplify the time values.

Speed unit of MILES per HOUR, time unit as HOURS, and distance as MILES:

               SPEED             TIME             DISTANCE

Michael        r+1               3%2F5               d

David           r                2%2F3               d

Next is formulate two equations and solve.
-
system%28%28r%2B1%29%283%2F5%29=d%2Cr%282%2F3%29=d%29

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!
Michael averaged running a certain distance 1 mph faster than David ran the same distance. If it took Michael 36 minutes to run the distance and it took David 4 minutes longer to run the same distance, how far did the boys run?
I don't even know how to begin to set up this problem into an equation, other than distance=rateXtime.
Let distance be D
Then Michael’s speed = D%2F%2836%2F60%29, or D%2F%283%2F5%29, or D+%2A+%285%2F3%29, or 5D%2F3
David’s speed = D%2F%28%2836+%2B+4%29%2F60%29, or D%2F%2840%2F60%29, or D%2F%282%2F3%29, or D+%2A+%283%2F2%29, or 3D%2F2
We then get: 5D%2F3+=+3D%2F2+%2B+1
10D = 9D + 6 ------- Multiplying by LCD, 6
10D – 9D = 6
D, or distance = highlight_green%28matrix%281%2C2%2C+6%2C+miles%29%29
Nothing complex....it's that easy! You want DISTANCE, so solve for nothing else but DISTANCE!