Set up two equations:
Sunshine College has 1100 students and gains 45 per year:
This can be written as 1100 + 45x ( where x is the number of years.)
Marigold has 2000 students and loses 15 per year.
This is written as 2000 - 15x ( where x is the number of years.)
Now set the two equations to equal each other and solve for x:
1100 + 45x = 2000 - 15x
Subtract 1100 from each side:
45x = 900 - 15x
Add 15 x to each side:
60x = 900
Divide each side by 60:
x = 900 / 60
x = 15
It will take 15 years.
