Question

The distance between two milestones is 230 km and two cars start simultaneously from the milestones in opposite directions. The distance between them after three hours is 20 km. If the speed of one car is less than that of other by 10 km/hr, then find the speed of each car.

• A. 25 km/hr, 40 km/hr
• B. 40 km/hr, 50 km/hr
• C. 20 km/hr, 40 km/hr
• D. 40 km/hr, 30 km/hr

Answer 1

The correct option is D 40 km/hr, 30 km/hr

$\text{Let the speed of one car be x km/hr.}$
$\text{Thus, speed of other car}=(x-10)km/hr$
$\text{Distance travelled by first car in 3 hours}=3xkm$
$\text{Distance travelled by second car in 3 hours}=3(x-10)km$
$\text{And, after 3 hrs the distance between}\text{the cars is 20 km.}$



$\therefore 3x+3(x-10)+20=230\Rightarrow 3x+3x–30+20=230\Rightarrow 3x+3x–10=230\Rightarrow 6x=240\Rightarrow x=40$

$\therefore \text{Speed of first car}=x=40km/hr\text{Speed of other car}=(x-10)=30km/hr$