how many seconds will a train 60 meters long take to cross a bridge 120 meters long if the speed of the train is 30 m / sec ?
"d = 60 + 120 = 180 s = 30 mps t = 180 / 30 = 6 sec a ) 6 sec"
divide(add(120, 60), multiply(30, const_0_2778))