Let X = Individual ticket and y = couples tickets.
Set up two equations:
X + Y = 47 tickets sold
1X + 8y = $200
Rewrite the first equation as X = 47-y
Replace x in the second equation and solve:
1(47-y) = 8y = 200
Simplify:
47 - y + 8y = 200
Combine like terms:
47 +7y = 200
Subtract 47 from both sides:
7y = 153
Divide both sides by 7:
y = 153 / 7
y = 21.857
Because Y does not equal a whole number, the extra dollar does belong in the box.