Question

2. If the speed of a car is increased by 10 km
per hr, it takes 18 minutes less to cover a
distance of 36 km. Find the speed of the car.​

Answer 1

Answer:

30km/hr

Step-by-step explanation:

Let speed of the car be x km/hr.

So,

x

36

−

x+10

36

=

60

18

⇒36(

x

1

−

x+10

1

)=

60

18

⇒

x

1

−

x+10

1

=

120

1

⇒

x

2

+10x

x+10−x

=

120

1

⇒

x

2

+10x

10

=

120

1

⇒x

2

+10x−1200=0

⇒x

2

+40x−30x−1200=0

⇒(x+40)(x−30)=0

Hence x=30km/hr