Tuen Mun Government Secondary School

Mike has 4 times as many stamps as Kevin does. If Mike gives 16 stamps to Kevin, he still has 25 more stamps than Kevin does. How many stamps does each of them have originally? A sum of money is just enough to buy 16 apples. If the price of each apple is reduced by $0.5, 2 more apples can be bought with the same amount of money. ................
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