ROI$=\frac{\text{C}\text{o}\text{n}\text{t}\text{r}\text{o}\text{l}\text{l}\text{a}\text{b}\text{l}\text{e}\text{m}\text{a}\text{r}\text{g}\text{i}\text{n}}{\text{A}\text{v}\text{e}\text{r}\text{a}\text{g}\text{e}\text{o}\text{p}\text{e}\text{r}\text{a}\text{t}\text{i}\text{n}\text{g}\text{a}\text{s}\text{s}\text{e}\text{t}\text{s}}=\frac{\text{C}\text{o}\text{n}\text{t}\text{r}\text{o}\text{l}\text{l}\text{a}\text{b}\text{l}\text{e}\text{m}\text{a}\text{r}\text{g}\text{i}\text{n}}{\text{a}\text{l}\text{e}\text{s}}\frac{\text{S}\text{a}\text{l}\text{e}\text{s}}{\text{A}\text{v}\text{e}\text{r}\text{a}\text{g}\text{e}\text{o}\text{p}\text{e}\text{r}\text{a}\text{t}\text{i}\text{n}\text{g}\text{a}\text{s}\text{s}\text{e}\text{t}\text{s}}$

$($b$1)$

Comparative data on three companies operating in the same industry follow. The minimum required ROI is $10\%$ for all three number eg $-45$ or parentheses eg$.(45).).$