Answer:
x+y< 400
Explanation:
x = Number of lawn tickets sold
y = Number of seat tickets sold
We are told that: Fewer than 400 tickets in total were sold.
Hence, this means that, less than 400 tickets were sold.
The symbol for less than = <
Therefore, the equation you could make for fewer than 400 tickets were sold is given as:
x+y< 400