well, its difference is 187 - 110 = 77.
now, if we take 110 as the 100%, what is 77 off of it in percentage?
[tex]\begin{array}{ccll} amount&\%\\ \cline{1-2} 110 & 100\\ 77& x \end{array} \implies \cfrac{110}{77}=\cfrac{100}{x}\implies \cfrac{10}{7}=\cfrac{100}{x} \\\\\\ 10x=700\implies x=\cfrac{700}{10}\implies x=70[/tex]
