While driving under normal conditions, your car gets two flat tires at the same time.
a) it is impossible
b) it is possible, but very unlikely
c) it is possible and likely

Ok lets limit out some of the answers. we know that this is perfectly possible, so a is not correct, we know that this is very unlikely, because have you or someone you know ever gotten two fllat tires at the same time? most likely not, so the answer is b

You can set up a system of equations for this problem. Let x = number of coach tickets and y = number of first-class tickets. Then:

 

330x + 1220y = 12730    (cost of coach tickets plus cost of first-class tickets is total budget)

x + y = 17    (number of coach tickets plus the number of first-class tickets is the total number of people)

 

 

Solve the second equation for y to get y = 17 - x, then plug that into the first equation and solve for x:

 

330x + 1220(17 - x) = 12730

330x + 20740 - 1220x = 12730

-890x + 20740 = 12730

-890x = -8010

x = 9

 

 

Sarah bought x = 9 coach tickets. Put that into the second equation and solve for y:

 

9 + y = 17

y = 8

 

 

Sarah bought y = 8 first-class tickets.

Hope this helps!! :D