maths
posted by Rox .
A group of friends are planning a road trip. If they all contributed $24, then they would be $6 short of the total. If they all contributed $25, then they would have $3 more than needed. What is the total cost of the trip?

C = Cost
n = nubers of friends
If they all contributed $24, then they would be $6 short of the total:
n * 24 = C  6 Add 6 to both sides
24 n + 6 = C  6 + 6
24 n + 6 = C
C = 24 n + 6
If they all contributed $25, then they would have $3 more than needed.
n * 25 = C + 3
25 n = C + 3 Subtract 3 to both sides
25 n  3 = C + 3  3
25 n  3 = C
C = 25 n  3
C = C
24 n + 6 = 25 n + 3 Subtract 24 n to both sides
24 n + 6  24 n = 25 n  3  24 n
6 = n  3 Add 3 to both sides
6 + 3 = n  3 + 3
9 = n
n = 9
Group have 9 friends
C = 24 n + 6
C = 24 * 9 + 6
C = 216 + 6
C = 222 $
OR
C = 25 n  3
C = 25 * 9  3
C = 225  3
C = 222 $
The total cost of the trip is 222 $ 
Cool I got the right answer not using cheat . im ready to the next level