Question 23599
1st find the time required for the horses to meet.
Let distance traveled by the 5.5 km horse be "x".
Then distance traveled by the 4.5 km horse will be 
"10-x"
Formula: time = distance/rate
EQUATION:
  Time for 5.5 horse = Time for 4.5 horse.
     x/5.5 = (10-x)/4.5
    4.5x = 55-5.5x
    10x = 55
      x = 11 km (distance for 5.5 km horse
So, time for 5.5 km horse is 11/5.5 = 2 hr.
In two hours the horsefly will go 60 km.

Cheers,
Stan H.
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