An Investor Has $500,000 to Invest and Wants to Maximize

An investor has $500,000 to invest and wants to maximize the money they will receive at the end of one year. They can invest in condos, apartments and houses. The profit after one year, the cost and the number of units available are shown below.
$\begin{array}{clccc}&& \text { Profit } & \text { Cost } & \text { Number}\\\text { Variable } & \text { Investment } & (\$ 1,000) & (\$ 1,000) & \text { Available } \\\hline \mathrm{X}_{1} & \text { Condos } & 6 & 50 & 10 \\\mathrm{X}_{2} & \text { Apartments } & 12 & 90 & 5 \\\mathrm{X}_{3} & \text { Houses } & 9 & 100 & 7\end{array}$
Based on this ILP formulation of the problem what formulas should go in cells E5:E12 of the following Excel spreadsheet?
MAX: $\quad 6 \mathbf { X } _ { 1 } + 12 \mathbf { X } _ { \mathbf { 2 } } + 9 \mathbf { X } _ { \mathbf { 3 } }$
Subject ta:
$\begin{array} { l } 50 X _ { 1 } + 90 X _ { \mathbf { 2 } } + 100 X _ { 3 } \leq 500 \\X _ { 1 } \leq 10 \\X _ { 2 } \leq 5 \\X _ { 3 } \leq 7 \\X _ { i } \geq 0 \text { and integer }\end{array}$