The variable, x, is the amount of carried good.
We know that x<550
also y will be the number of people.
so x=336+y*25 (the total weight is the equipment plus 25 lbs for food for each person)
so we can substitute:
x<550
x=336+y*25
336+y*25<550
subtract 336 from both sides
y*25<214
divide by 25
y<8.56
so it has to less than 8 people.
The greatest number of people in the expedition is 8.
