Question

a car left town A at 10:00 am and travelled towards town B at the average speed of 70 km/h. At the same time a truck left town B at an average speed of 50 km/h . If the distance between town A and town B is 420 km, at what time would the car and the truck pass each other? Please help !

Answer 1

The important formula to this problem is $distance=rate(time)$ or $d=rt$

Now, the speed of the car is 70 km/h, and the speed of the truck is 50 km/h. It will take the two vehicles the same amount of time to meet since they both left at the same time. So, since distance equals rate times time, and t = time:

the distance of the car = 70t
the distance of the truck = 50t

Because they both left in opposite directions, and the towns are 420 kilometers apart, the equation for this would be

$70t+50t=420$

We now solve the equation.

$70t+50t=420 \\ 120t=420 \\ \frac{120t}{120}= \frac{420}{120} \\ t=3 \frac{1}{2}$

It will take the vehicles 3 and a half hours to meet. Since we're looking for the time, 3 and a half hours from 10:00 AM is 1:30 PM.

So, the car and the truck will pass each other at 1:30 PM.