Let x be the sales last year .
Then :-
[tex] \frac{28}{100} \: of \: x = \: \: 70560[/tex]
[tex] \frac{28}{100} x = 70560[/tex]
[tex]x = \frac{70560 \times 100}{28} [/tex]
[tex]x = \frac{7056000}{28} [/tex]
[tex]x = 252000[/tex]
Therefore , the sales last year was $252,000 .