Question

A train crosses two cyclists travelling in the same
direction as the train, in 12 seconds and
15 seconds respectively. If the speeds of the two
cyclists are 10 kmph and 12 kmph respectively,
then find the length and the speed of the train.​

Answer 1

.Let the length of the train be x metres and speed be y m/s

Speed of the first person=2kmph

=2×

18

5

=

9

5

m/s

Speed of the second train =4kmph

=4×

18

5

=

9

10

m/s

y−

9

5

x

=9

9y−5=x

90y−50=10x...........................................(1)

y−

9

10

x

=10

90y−100=9x...........................................(2)

Substracting 1 and 2

90y−50−90y+100=10x−9x

x=50

So, the length of the train=50m

Answer 2

Answer:

50 IS THE CORRECT ANSWER