Question

mark had to travel 220km in 4.5hr , using a train that travels at the speed of 60 km/hr ar a bus that travel at the Speed of 40 km/ hr ,or any combination of the two mode of transport.for how long did he travels by bus ?

Answer 1

Answer:

2.7 hours

Step-by-step explanation:

Total time of journey = 4.5 hrs

Total distance of journey = 220 km

Speed(train) = 60 km/hr

Speed(bus) = 40 km/hr

Using formula, distance = speed × time,

Time taken by train(independently) = Time(train) = 220/60

= 11/3 hrs

= 3.66 hrs < 4.5 hrs

Time taken by bus(independently) = Time(bus) = 220/40

= 11/2 hrs

= 5.5 hrs > 4.5 hrs

As no mode of transport can cover journey in exactly 4.5 hrs, therefore, combination of mode of transport will be needed.

Find ratio of Time(train) and Time(bus),

Time(train) : Time(bus) = (11/3) / (11/2) = 2/3, or 2 : 3

So from ratio, we can infer that

Time(train) = (2/3)[Time(bus)]

Now as per question,

Time(train) + Time(bus) = 4.5 hrs

So using the ratio,

(2/3)[Time(bus)] + Time(bus) = 4.5

[5 × Time(bus)] / 3 = 4.5

5 × Time(bus) = 4.5 × 3 = 13.5

Time(bus) = 13.5/5 = 2.7 hours

So, Mark travels 2.7 hours by bus.