The Given equation is , 3 x + x = 440,
Let speed of train A is x Km/hour and Speed of train B which is a Bullet train which starts from same station but from different platform is 3 times the speed of train A.
And Sum of their Velocities is i.e Velocity of train A and Velocity of train B is 440 Km/hour.
Answer: 4 black marbles, 3 blue, 2 green, and one red.
Step-by-step explanation:
There are 3 co-efficients in this expression