1,000,000,000,000 is the answer
Well you will just subtract 91 - 7 which equals 84.
So 7 + 84 = 91
816/850x100 = 96
Therefore 96 % of tickets were sold.
Answer
Fill the 5 gallon jug.
Pour the 5 gallon jug into the 3 gallon jug.
Empty the 3 gallon jug and pour the remaining 2 gallons in the 3 gallon jug.
Fill the 5 gallon jug and pour 1 gallon into the 3 gallon jug (remember it will only take one gallon)
Viola the remaining 5 gallon jug will have exactly 4 gallons remaining.