how long does a train 150 m long traveling at 50 kmph takes to cross a bridge of 250 m in length ?
"d = 150 + 250 = 400 m s = 50 * 5 / 18 = 125 / 9 t = 400 * 125 / 9 = 28.8 sec answer : a"
divide(add(150, 250), multiply(50, const_0_2778))