It will take her around 18.925 or by rounding you get around 19 liter containers to fill up the 5 gallon bucket.
Work: I did this by finding the maximum amount of Liters the bucket can hold. Since the bucket holds 5 gallons and those gallons consisting of 3.785 liters, I multiplied 5x3.785 to get the maximum capacity in liters that the bucket can fill. Since the containers pouring the water are only 1 liter, we divide by 1 (which is useless but if it’s any number beside 1 do this step) by the total so we do 18.925/1 to get 18.925. If your teacher wants you to round, it’ll be 19