from 1200 to 850, 1200 - 850 = 350.
if we take the 1200 to be the 100%, what is 350 off of it in percentage?
[tex]\bf \begin{array}{ccll} amount&\%\\ \cline{1-2} 1200&100\\ 350&x \end{array}\implies \cfrac{1200}{350}=\cfrac{100}{x}\implies \cfrac{24}{7}=\cfrac{100}{x} \\\\\\ 24x=700\implies x=\cfrac{700}{24}\implies x = \cfrac{175}{6}\implies x = 29.1\overline{6}[/tex]
