how long does a train 100 m long traveling at 60 kmph takes to cross another train of 170 m in length has a speed of 40 kmph ?
"d = 100 m s = ( 60 + 40 ) * 5 / 18 = 250 / 3 t = 100 * 9 / 250 = 3.6 sec answer : e"
divide(add(100, 170), multiply(60, const_0_2778))