Number of seats on a plane - 120
Average load factor - 75%
So in other words, every flight on average has 90 people on it.
Average fare per passenger $70
Average costs per passenger $30
In other words, we make on average $40 per passenger.
So for a flight, we usually have 90 people, and we make $40 per person, so 90 * $40 means $3600 profit per flight.
We need to cover $1,200,000 in expenses per month, making $3600 per flight.
1200000 / 3600 = 333.3 flights before you break even (i.e. 333rd flight you're at a loss, 334th you've made a small profit).
Moral of the story, the aviation business sucks.