a train 280 m long , running with a speed of 72 km / hr will pass a tree in
"sol . speed = ( 72 x 5 / 18 ) m / sec . = 20 m / sec . time taken = ( 280 x 1 / 20 ) sec = 14 sec answer a"
multiply(divide(280, multiply(72, const_1000)), const_3600)