If a shirt costs $40 after a 20% discount, what was the original price?

To determine the original price of a shirt that costs $40 after a 20% discount, it's important to understand how discounts work. A discount of 20% means that the shirt is being sold for 80% of its original price because 100% - 20% equals 80%.

So, if we let ( P ) represent the original price, we can set up the equation:

[ 0.80P = 40 ]

To find the original price ( P ), we need to solve for ( P ):

1. Divide both sides of the equation by 0.80 to isolate ( P ):

( P = \frac{40}{0.80} )

2. Calculating that gives:

( P = 50 )

Thus, the original price of the shirt was $50. This means that after applying a 20% discount to the original price, the new price is $40. This confirms that the original price was indeed $50, making it the correct answer.