Question 98812
First thing is to set up some variables
So western state college's age will be w
and southern state's age will be s
From the given information we can write these equations:
w = s + 18   and   w = 2.5s
Now if s + 18 equals w 
and 2.5s equals w then we know that
2.5s = s + 18
Now we can solve for s
first subtract s from both sides of the equal sign like this
2.5s - s = s - s + 18
1.5s = 18
now divide both sides by 1.5
1.5s/1.5 = 18/1.5
s = 18/1.5
s = 12
now that we have a value for s we can use that to solve for w so
w = s + 18
w = 12 + 18
w = 30