Answer:
I believe the answer is about 95 percent.
Explanation:
The reason for this answer is because as said 22 and a fifth would mean the tank is full. This means I set up a proportion. What I did was...
22 1/5 over 100 = 21 over x
Now: I do 21 multiply by 100 divided by 22 1/5 to get the answer
What I just wrote is the rule of proportions
Finally, after doing all of that, the answer I got was 94.59459459, but I rounded to the answer of 92 percent.