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

1. 0.3 •4 is the same as 4 groups of 0.32. 7•0.8 is the same as 7 groups of 0.83. it increases by 0.5 every time, so 0.5x4 it increases by 0.9 every time, so 0.9x5. 0.9•12=10.86. 0.47•5=2.35i can finish the next ones in a separate post

12+3b -1=-5-b -12-1+5=-b-3b -8=-4b