a train travels certain average speed for a distance of 80 km and then travels a distance of 24 km at an average speed of 5km/hr more than its original speed. if it takes 4 hrs. more to complete the total journey, what is its original speed???
Apshrivastva:
quite wrong question..... the train cover 80km distance with what speed???
Answers
Answered by
3
original time is 80/x
where x is speed
according to the question
original time+4=new time
80/x +4=24/(x+5)
80/x=24/(x+5) -4
80/x=(24-20-4x)/(x+5)
80/x=(4-4x)/(x+5)
80(x+5)=(4-4x)x
80x+400=4x-4x2
4x2+76x+400=0
x2+19x+100=0
The equation coming has imaginary roots
where x is speed
according to the question
original time+4=new time
80/x +4=24/(x+5)
80/x=24/(x+5) -4
80/x=(24-20-4x)/(x+5)
80/x=(4-4x)/(x+5)
80(x+5)=(4-4x)x
80x+400=4x-4x2
4x2+76x+400=0
x2+19x+100=0
The equation coming has imaginary roots
Answered by
2
hey mate
this is not possible because this equation doesn't have equal roots
this is not possible because this equation doesn't have equal roots
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