a train speeds past a pole in 15 seconds and a platform 140 meters long in 25 seconds . what is the length of the train ( in meters ) ?
"let the length of the train be x meters . the speed of the train is x / 15 . then , x + 140 = 25 * ( x / 15 ) 10 x = 2100 x = 210 meters the answer is c ."
multiply(140, subtract(const_2, const_1))