Calculate the Dollar Markup and Cost

Short Answer

Calculate the dollar markup and cost.
$$\begin{array} { | c | c | c | c | } \hline \text { Selling Price } & \begin{array} { c } \% \text { Markup on } \\\text { Selling Price }\end{array} & \begin{array} { c } \text { Dollar } \\\text { Markup }\end{array} & \text { Cost } \\\hline \$ 900 & 30 \% & \text { A } & \text { B } \\\hline\end{array}$$