Train A leaves a station 45 minutes before train B. Both trains travel in the same direction and their speeds are 36km/h and 48km/h respectively. i) How long will it take train B to catch up with train A? ii) How far from the start were the two trains when they met

Train B catches up with train A at 2.25 h

The two trains meet at 108 Km from the start

Step-by-step explanation:

Relative Speed

There are two trains, A and B leaving the same station. Train A leaves 45 minutes before train B at va=36 Km/h. Train B travels at vb=48 Km/h in the same direction, so they eventually meet.

i)

Calculate the head start of train A Xh, i.e. the distance it traveled in 45 minutes = 45/60=0.75 h.

When train A is 27 Km ahead, train B leaves the station. The relative speed between them is vb-ba=48 - 36 = 12 Km/h.

Thus, for train B to meet with train A, the head start must be traveled at the relative speed.

The time needed to do that is:

t = 2.25 h

Train B catches up with train A at 2.25 h

ii) In the time calculated above, train B has traveled a distance of:

The two trains meet at 108 Km from the start

step-by-step explanation:

you can add the two numbers and divide the result by 2. or you can find the gap between the two numbers and add half of this to the smaller number.

x is greater than 5

step-by-step explanation:

2x+7 is greater than 17

    -7                           -7

2x is greater than 10

divide by 2 each side

x is greater than 5