Divide the total the lake holds by the number of days:
400 million / 25 days = 16 million gallons per day.
You divide everything by 2.
Your answer is
Y=1/2 + 3/2
So in a proportion 23.4 over 5.49 equals 1 over o and multiply 5.49•1=23.4o
5.49=23.4o divide by 23.4 on both sides and that equals 4.26 per oz