If your salary of 33,000 this year was 10% more than last year, what was last years salary?
If last year salary was 100 then this year it will be 110
so when this year salary is 110 last year it was 100
then if this year salary is 33000, then last year it was 33000 × 100/110
= 300 × 100 = 30000
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Yet another way: Suppose you salary last year was "A". 10% of that is 0.01A and your last years salary plus 10^% is A+ 0.10A= (1+ .1)A=1.1A. Since 33,000 is "10% more than last year, 1.1A= 33000. Divide both side by 1.1 to get mush's solution.