Anshu covers a distance of 200 km travelling with a uniform speed of X km per hour the distance could have been covered in 2 hour less than the speed been(x + 5) km per hour calculate the value of x
Answers
Answer:
The value of x is 20
Step-by-step explanation:
Given : Distance = 200km , Speed = x Km/h
Let time taken to cover 200km with speed x km/h is y.
as we know speed = Distance /time
x = 200/y _eq(1)
now, according to question speed is increased which is (x+5)km/h then the distance covered by new speed takes 2 hours less then the original
∵ time =y-2 hrs , speed = (x+5) km/h
(x+5)= 200/y-2 _eq(2)
Now , Putting eq(1) in eq(2)
we get (200/y)+5 = 200/y-2
(y-2)(200+5y) = 200y
200y + 5y² -400 -10y = 200y
200y -200y +5y² -10y -400 = 0
5y² -10y -400 = 0
y²-2y - 80=0
y² -10y +8y - 80 =0
y(y-10) + 8(y-10) = 0
(y-10)(y+8) =0
y =10,-8
∵ y = 10 (because y is time and we take time in positive )
putting the above value im eq(1)
x= 200/10
x = 20
speed is 20km/h.