So to start, we write out everything we know. We know that:
We had coach tickets for $370 and first class tickets for $1170. So we also know that they we're 15 people on the trip, including Sarah, and we assume that a certain amount of people that went on the trip got first class tickets, while the rest got coach tickets. So then, we let x be the number of people who got the coach tickets and y be the number of people who got the first class tickets. So:
x+y=15, for people who got each type of ticket and,
370x+1170y=11950, for the total amount of money spent.
Now we have a system of equations, and we can solve this problem. So we can multiply the first equation by -370.
-370x-370y=-5550. We then add this to the other equation to get rid of x, and we are left with:
800y=(11950-5550)=6400
800y=6400
y=8, so 8 people got first class tickets, while 7 people got coach tickets, since x+8=15, meaning she bought 8 first class tickets and 7 coach tickets. I hope this helped you!
