RRB Group-D Model Paper 16 with answers for online practice

Let the speed of A be 3x km/hr
Speed of B = 7x km/hr
Let B takes y hours to cover a distance
According to problem,
⇒ 3x × (y + 16) = 7x × y
⇒ 3y + 48 = 7y
⇒ 4y = 48
⇒ y = 12
∴ Time taken by B to cover the distance = 12hours