For this chain-of-thought reasoning and answer, what was the question?
Two pairs of sunglasses costs 2 x $50 = $100. So, Mary spent $100 + $100 = $200. Thus, two decks of basketball cards costs $200 - $150 = $50. Therefore, one deck of basketball cards costs $50 / 2 = $25.
 A: 25
Q: Mary and Rose went shopping to buy presents. They spent the same amount. Mary bought two pairs of sunglasses for $50 each and a pair of jeans for $100. Rose bought a pair of shoes at $150 and two decks of basketball cards. How much did one deck of basketball cards cost?