two trains t 1 and t 2 start simultaneously from two stations x and y respectively towards each other . if they are 70 km apart both 3 and 6 hours after start , then find the distance between the two stations .
in first 3 hours t 1 travels r km and t 2 travels s km . after 6 hours they traveled r + s + 70 + 700 2 ( r + s ) = r + s + 140 r + s = 140 hence distance between xy is r + s + 70 = 140 + 70 = 210 answer : a
add(multiply(70, 2), 70)