Ardi and Lei are both travelling by train.
Ardi’s train travels 70 km in 35 minutes.
Lei’s train travels 585 km.
It leaves at 9:05 and arrives at 13:35.
Work out the difference, in km/h, between the average speed of their trains.
Question
Question
Ardi and Lei are both travelling by train.
Ardi’s train travels 70 km in 35 minutes.
Lei’s train travels 585 km.
It leaves at 9:05 and arrives at 13:35.
Work out the difference, in km/h, between the average speed of their trains.
Answer:
10 kilometer/hour
Step-by-step explanation:
Average speed = Total distance travelled / Total time taken
Ardi:
Total distance travelled = 70 km
Total time taken = 35 minutes = 35/60 hour
Average speed = Total distance travelled / Total time taken
= 70 km ÷ 35/60 hr
= 70 × 60/35
= 4,200/35
= 120 kilometer/hour
Lei:
Total distance travelled = 585 km Total time taken = 9:05 – 13:35 = 4 hours 30 minutes
= 4.5 hours
Average speed = Total distance travelled / Total time taken
= 585 km / 4.5 hours
= 130 kilometer/hour
Difference, in km/h, between the average speed of their trains = Lei’s train – Ardi’s train
= 130 kilometer/hour – 120 kilometer/hour
= 10 kilometer/hour