Places A and B are 80 …

Let the speed of first car be x km/h and that of second car be y km/h. Now, Distance = speed×time 1st case(in the same direction): 80=(x-y)×8 => 8x-8y=80---------------(i) 2nd case(in opposite direction): 80=(x+y)×4/3 (1h,20min=4/3hours) => 4x+4y=240-------------(ii) Now, From equ. (i) & (ii) 8x-8y=80 ---------(i) 4x+4y=240 ---------(ii) ×2 Muliplying equation (ii) by 2 8x-8y=80 8x+8y=480 --------------------------------- 8x+8x=480+80 => 16x=560 => x=560/16 => x=35 Putting value of x in equ.(i), 8(35)-8y=80 => 280-8y=80 => -8y=80-280 => -8y=-200 => y=200/8 => y=25 Hence, speed of 1st car(x)= 35 km/h and speed of second car(y)= 25 km/h