Answer:
8 pounds
Step-by-step explanation:
8.75 / 3.5 = 2.5
20/2.5 = 8
distance = rate times time.
Here the distance covered by the first train is (70 km/hr)t (t=# of hours), and that by the second train is (85 km/hr)t.
Add these together and set the sum equal to 620 km:
70t + 85t = 620, or 155t = 620, or 4. It will take 4 hours for the distance between the two trains to increase to 620 km.
11 and 9 are coefficient
Because they both have a variable to them.
