B

Let their speed be x km/hr and y km/hr respectively

Then 60 / (x+y) = ½

X+y = 120 ------------->1

Now when they move in same direction

(distance travelled by A in 3 hrs) – (Distance travelled by B in 3 hrs) = 60km

3x – 3y =60

X – y =20 ------------>2

Adding 1 & 2 we get

2x = 140

X=70

Put x value in 1 we get

Y=120 -70=50

Y=50

Therefore A’s speed = 70 km/hr

Let their speed be x km/hr and y km/hr respectively

Then 60 / (x+y) = ½

X+y = 120 ------------->1

Now when they move in same direction

(distance travelled by A in 3 hrs) – (Distance travelled by B in 3 hrs) = 60km

3x – 3y =60

X – y =20 ------------>2

Adding 1 & 2 we get

2x = 140

X=70

Put x value in 1 we get

Y=120 -70=50

Y=50

Therefore A’s speed = 70 km/hr