a train 120 m long crosses a platform with a speed of 60 kmph in 15 sec ; find the length of the platform ?
d = 120 + x t = 15 s = 120 + x / 15 * 18 / 5 = 60 kmph . = > ( 120 + x ) * 18 = 4500 = > 120 + x = 250 = > x = 130 m answer : b
subtract(multiply(15, multiply(60, const_0_2778)), 120)