Hi Amanda.
The plane can only carry 360 passengers, so the inequality would be a less than or equal to symbol with the sum of the unknown number and the 240 passengers already on the plane on the left side and 360 on the right side.
Therefore, it would look like this: x + 240 ≤ 360
In order to get x on a side by itself you would subtract from both sides which would make the solution:
x ≤ 120, which would mean the amount of passengers that can be added to this plane is less than or equal to 120.
I hope this helps you understand this particular problem.
Sincerely,
Shaniqua