Algebra  please check my answer for me
posted by Terence P. .
The population increased 80 percent in 5 years. The current population is 18,000. find five years ago.
18,000 * 0.80 = 14,400
18,000  14,400 = 3,600
3,600 is the population five years ago?
to check:
3,600 * 5 = 18,000
Is 3,600 the correct answer. Was this problem done correctly?

No, you did not do it correctly.
Let X be the population 5 years ago.
X*(1.8) = 18,000
X = 10,000 
A city's population is currently 22,000 and is growing by 4.6% each year. In how many years will the town's population reach 55,000?