Questions

Let speed of train B be x m/s And length of train B be y m
Then length of train A is 2y m
Speed of train A = 84 × 5/18 = 210/9 m/s = 70/3 m/s
A.T.Q, (2y+y)/10 = 70/3 − x .............(i)
and (2y+y)/ 22.5 = 70/3 − 2x ................(ii)
solving (i) and (ii), y = 50 m

The Jigme Dorji National Park is the second-largest National Park of Bhutan. The park provides sanctuary for 37 known species of mammals including several endangered, threatened or vulnerable species, such as the takin, snow leopard, clouded leopard, Bengal tiger, bharal or Himalayan blue sheep, etc. It is also home to the Indian leopard, serow, sambar, barking deer, goral, marmot, pika and more than 300 species of birds. It is also the only park in Bhutan where the national animal (takin), flower (blue poppy), bird (raven) and tree (cypress) exist together.

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