Atrain traveled from station a to station b at an average speed of 80 kilometers per hour and then from station b to station c at an average speed of 60 kilometers per hour. if the train did not stop at station b, what was the average speed at which the train traveled from station a to c?
(1) the distance that the train traveled from station a to station b was 4 times the distance that train traveled from station b to station c.
(2) the amount of time it took to the train to travel from station a to station b is 3 times the amount of time that it took the train to travel from station b to station c.

1)

75 kmh⁻¹

2)

75 kmh⁻¹

Explanation:

1)

= Speed of train from station A to station B = 80 kmh⁻¹

= distance traveled from station A to station B

= time of travel between station A to station B

we know that

= distance traveled from station B to station C

= Speed of train from station B to station C = 60 kmh⁻¹

Total distance traveled is given as

Total time of travel is given as

Average speed is given as

Given that :

So

2)

= Speed of train from station A to station B = 80 kmh⁻¹

= time of travel between station A to station B

= distance traveled from station A to station B

we know that

= distance traveled from station B to station C

= Speed of train from station B to station C = 60 kmh⁻¹

= time of travel for train from station B to station C

we know that

Total distance traveled is given as

Total time of travel is given as

Average speed is given as

Given that :

So