Question

The rectangle of x's below is 5/3 of another (original) rectangle of x's

Answer 1

There are 10 rows of 3 colums of "x"'s, so.. 3x10 or 30 "x"s, and we know that's 5/3 of the original... the original will be one whole or 3/3 or 1

thus    $\bf \begin{array}{ccllll} size&x's\\ \textendash\textendash\textendash\textendash\textendash\textendash&\textendash\textendash\textendash\textendash\textendash\textendash\\ \frac{5}{3}&30\\\\ \frac{3}{3}&x \end{array}\implies \cfrac{\frac{5}{3}}{\frac{3}{3}}=\cfrac{30}{x} \implies \cfrac{5}{3}=\cfrac{30}{x}$

solve for "x"