其它
Tadek has $$7$$ zloty (unit of money) more than Witek. Witek has $$10$$ zloty less than Karol. Witek and Karol have $$28$$ zloty together. How much money does Tadek have? 
Overseas Competition->Knowledge Point->Word Problem Modules->Questions Involving Sum, Difference and Multiples->Problems Involving Sum and Difference->Sum and Differences Problems with multiple Variables
Witek has $$(28 - 10) \div 2 = 9$$ zloty, so Tadek has $$9 + 7 = 16$$ zloty. 