1.

If the speed of a car is increased by 10km/hour it takes 18minutes less to cover a distance of 36km then find the speed of the car

Answer»

LET speed be x


so,if speed is x+10 then it TAKES 18 minutes less


so, 36/x-36/x+10=18/60


36x+360-36x/x^2-10x=3/10


3600=3x^2-30x


1200=x^2-10x


x^2-10x-1200=0


x^2+30x-40x-1200=0


x(x+30)-40(x+30)=0


x=-30 or 40


as speed cannot be negative,

x=40


the original speed of CAR is 40 KMPH


Discussion

No Comment Found

Related InterviewSolutions