<human>:  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?
<bot>: How much did Mary spend on sunglasses? ** Two pairs of sunglasses costs 2 x $50 = $<<2*50=100>>100.
How much did Mary spend? ** So, Mary spent $100 + $100 = $<<100+100=200>>200.
How much did one deck of basketball cards cost? ** Thus, two decks of basketball cards costs $200 - $150 = $<<200-150=50>>50.
How much did one deck of basketball cards cost? ** Therefore, one deck of basketball cards costs $50/2 = $<<50/2=25>>25.
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