The population of a small town increased by 25% two years ago and then decreased by 25% last year. Now the population is 4500 people. What ws the population before the two changes.
Call the original population x. If it increased by 25%, it was 1.25x. If it then decreased by 25% of that, it's now 0.75(1.25x), or 0.9375x. 0.9375x = 4500 x = 4500/0.9375 = 4800
