If you would like to know the expression that could be used to determine the cost of a $50 video game after a 20 percent discount, you can do this using the following steps:
$50 - 20% of $50 = $50 - 20% * $50 = $50 - 20/100 * $50 = $50 - 1/5 * $50 = $50 - 0.20 * $50 = $50 * 0.80 = $40
The correct result would be $50(0.80).