A rower travels upstream at 6 km per hour and back to the starting place at 10 km per hour. The total journey takes 48 minutes. How far upstream did the rower go?

Question

directrix · Answer

@jamesmstone
Suggested solution courtesy of @czar  
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Use the equation d = rt where d = distance, r = rate or speed, and t = time. Solve for d upstream.
 
d + d = r(up & down) * t (total).
 
d / 6 + d / 10 = 48/60 hours. Multiply all terms by common denominator of 60 to cancel out denominators.
 
10d + 6d = 48
 
16d = 48.
 d = ?