Question 1133497
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Let "x" be the averaged speed on the inclined road, in km/h (the value under the question).

Then the averaged speed on the declined road is 1.2x km/h.


The time equation  is


    {{{7.5/x}}} + {{{8.7/(1.2x)}}} = 9 - 3 = 6.


Multiply both sides by  1.2x. You will get


    1.2*7.5 + 8.7 = 6*1.2*x,    or

    9       + 8.7 = 7.2x    


    x = {{{(9+8.7)/7.2}}} = 2.4583 kilometers per hour.     <U>ANSWER</U>
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