Question

Places A and B are $80$km apart from each other on a highway . A car starts from A and B other from B at the same time. If they move in the some direction, they meet in $8$hours and if they move in opposite direction they meet in $1$ hour and $20$ minutes Find the speeds of the car

Answer 1

Let speed of car starting from $A$ be $x$ km/hr and speed of car starting from $B$ be $y$ km/hr
$Distance=80km$
According to the question,

When cars move in the same directions,
$80=(x-y)\times 8$

$(x-y)=10$ ......(1)

When cars move in the opposite directions,

$80=(x+y)\times \frac{4}{3}$ [1 hour and 20 minutes $=\frac{4}{3}Hours$]
$x+y=60$ ......(2)

Adding equation (1) and (2), we get

$2x=70$

$x=35km/h$

On substituting the value of $x$ in equation (1), we get

$y=25km/h$

Hence, speed of car starting from $A$ is $35$ km/hr and speed of car starting from $B$ is $25$ km/hr.