Question 30: Mai uses 25,000 VND to buy a pen. There are two types of pens: Type I costs 2,000 VND each, Type II costs 1500 VND each. How many pens can Mai buy at most if Mai only buys type I pens?
We have 25000 : 2000 = 12 (remainder 1000)
So Mai can buy at most 12 type I pens.
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