Question

45% of c is 72. Find the value of c

Answer 1

well, let's call "c" the 100%, and we know that 45% of that is 72, hmmm so

`\begin{array}{ccll} amount&\%\\ \cline{1-2} c & 100\\ 72& 45 \end{array} \implies \cfrac{c}{72}~~=~~\cfrac{100}{45} \\\\\\ \cfrac{ c }{ 72 } ~~=~~ \cfrac{ 20 }{ 9 }\implies 9c=1440\implies c=\cfrac{1440}{9}\implies c=160`

Answer 2

c = 72/0.45

c = 160

So the value of c =160