If a store buys an item for $50 and marks it up by 100%, the price can be calculated as follows:
First, we determine the amount of the markup. A 100% markup on the cost means that the store will add an amount equal to the cost of the item to the original price. Since the item costs $50, the markup is also $50.
Now, we add the original price to the markup: $50 (original price) + $50 (markup) = $100.
Therefore, the price of the item after the 100% markup is $100.