# Two trains are running at 40 km/hr and 20 km/hr respectively in the same direction. Fast train completely passes a man sitting in the slower train in 5 seconds. What is the length of the fast train ?

$27\frac{7}{9}$

$28\frac{7}{9}$

$29\frac{7}{9}$

$30\frac{7}{9}$

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