Answer:
Original cost = $40
Step-by-step explanation:
Let the original cost be $x.
Therefore,
[tex]x - \frac{10}{100} \times x = 36 \\ \\ x - \frac{1}{10} x = 36 \\ \frac{10x - x}{10} = 36 \\ \frac{9x}{10} = 36 \\ 9x = 360 \\ x = \frac{360}{9} \\ x = \$ 40[/tex]
