Question

Alex got 27 questions out of 30 correct. what present of the questions did he get correct?(use fish method)

Answer 1

if we take 30 to be the 100%, what is 27 off of it in percentage?

$\begin{array}{ccll} amount&\%\\ \cline{1-2} 30 & 100\\ 27& x \end{array} \implies \cfrac{30}{27}=\cfrac{100}{x} \\\\\\ \cfrac{10}{9}=\cfrac{100}{x}\implies 10x=900\implies x=\cfrac{900}{10}\implies x=90$