Marlene had $25. ron had twice as much money as marlene, but he bought lunch for both of them at $7.50 each. who has more money after lunch?

Ron has more money because he had twice as much as Marlene. So Ron has $50 and Marlene has $25. If lunch cost $7.50 per person and Ron is paying for two people then that means Ron will be paying $15 for lunch, and $50 - $15 is $35. Therefor Ron has more money. 
  
Ron is the answer

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