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A cargo train and a passenger train, which start from two stations that are 710 km apart, are traveling towards each other. The cargo train started an hour before the passenger train, and is traveling with a speed of 110 km/hour. In how many hours will the cargo train and the passenger train meet, if the passenger train is traveling at 90 km/hour?

plz help

Respuesta :

joseaaronlara

Answer:

The answer to your question is 4 hours (considering the cargo train started 1 hour before).

Step-by-step explanation:

Data

distance = 710 km

Cargo train = 1 hour before  speed = 110 km/h

time = ?

Passenger train     speed = 90 km/h

Process

1.- Calculate the distance traveled by the cargo train in 1 hour

     d = vt

      d = (110)(1)

         = 110 km

2.- Write an equation to solve this problem

distance traveled by the cargo train + distance traveled by the passenger

                                                                 train = total distance

            (110 + vct) + (vpt) = 710 km

Substitution

             110 + vct + vpt = 710

             110 + 110t + 90t = 710

              200t = 710 - 110

               200t = 600

                      t = 600 / 200

                      t = 3 hours

3.- Conclusion

The trains will meet after 4 hours, because we must consider that the cargo train started 1 hour before.            

Answer: it will take 4 hours for them to meet.

Step-by-step explanation:

By the time the cargo train and the passenger train meet, they would have covered a total distance of 710km.

Let t represent the time it takes them to meet.

Distance = speed × time

The cargo train is traveling with a speed of 110 km/hour. This means the distance the cargo train covers in t hours is 110 × t = 110t

The cargo train started an hour before the passenger train. This means that the time spent by the passenger train is (t - 1) hours. if the passenger train is traveling at 90 km/hour, then the distance covered by the passenger train is

90(t - 1)

Since the total distance covered is 710 km, then

110t + 90(t - 1) = 710

110t + 90t - 90 = 710

200t = 710 + 90 = 800

t = 800/200

t = 4

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