Question 1071915
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The total travel time for a family to reach a campsite is 2 hours. They drove for 81 kilometer and hiked for 2 kilometer. 
If they drove 50 kilometer per hour faster than they hiked, what is their average driving speed?
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{{{81/r + 2/(r-50)}}} = 2.


Solve for "r". For it, multiply both sides by r*(r-50), then simplify and solve the quadratic equation which you obtain.




Post by "josgarithmetic" is WRONG.