Answer: All the time.
Explanation:
Here,
x= elapsed time
y = number of gallons of water in tank.
For tank A,
3y=750x+300
Divide both sides by 3, we get
y= 250x+100 ...(i)
For tank B,
4y=1000x+400
Divide both sides by 4, we get
y=250+100 ...(ii)
From (i) and (ii) it can be seen that both the function are same.
That means the amount of watre will be same for every value of x, where x ≥0