Question

What percent of 210 is 70?

Answer 1

If we take 210 to be the 100%, what is 70 off of it in percentage then?

$\bf \begin{array}{ccllll} amount&\%\\ \text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\ 210&100\\ 70&x \end{array}\implies \cfrac{210}{70}=\cfrac{100}{x}\implies x=\cfrac{70\cdot 100}{210}$

Answer 2

Percent means parts out of 100
so x%=x/100

'of' means multiply

so

what percent of 210 is 70 translates to
x/100 times 210=70
210x/100=70
21x/10=70
times 10 both sides
21x=700
divide both sides by 21
x=33.333333


33.33333333% of 210 is 70