Question

Find last year's salary if after a 4% raise , this year's salary is $44,200.

Answer 1

You can try this way:
x - last year´s salary,  raise: 4% = 0.04     ( 100%+4% = 104% = 1.04 )
x · 1.04 = 44,200
x = 44,200 : 1.04
x = 42,500
Last year´s salary was $42,500.