It is known that 60 minutes equals 1 hour.
Therefore, the first thing we do to solve the problem is to calculate how many hours are equivalent to 96 minutes.
For that we calculate:
[tex]96 minutes * \frac{1 hour}{60minutes}=\frac{96}{60}=1.6hours\\[/tex]
Thus:
96 minutes = 1.6 hours.
1.9 ounces of water are lost every 1.6 hours.
Therefore, in 8 hours the amount of water lost is:
[tex]\frac{8hours}{1.6hours}*1.9 = 9.5\\[/tex] ounces of water
After 8 hours, 9.5 ounces of water are lost
Therefore, the amount of water left in the tank after 8 hours is:
[tex]80 000-9.5=79990.5[/tex] ounces
