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问题描述：
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1.Mike has 2.05 dollars in dimes and
quarters.If he has four fewer dimes than quarters,how much money does he have
in dimes?答案是3dimes,so he has 30 cents in dimes.
2.05 dollars in dimes and quarters是什么意思?最后的答案30cents in
2.Mr.Jones sold two house for 80000 dollars
each.One house was sold at a 20 percent loss and the other at a 20 percent
gain.What is the gain minus the loss?
答
第一题 dimes是10美分硬币,quarters是25美分硬币,他一共有2.05美元（也就是20.5美分）,他的10美分硬币比25美分少四个,问你他10美分硬币一共有多少钱
设他有X个25美分硬币,（X-4）个20美分硬币
25X+10(X-4)=20.5
X=7,X-4=3
所以他有三个10美分（30 cents in dimes）
第二题Mr.Jones以80000元卖了两套房子,一套赚了20%,一套亏了20%,问赚的减亏的剩多少钱?
赚的那套原价为 80000/(1+20%)=66666
赔的那套原价为 80000/（1-20%）=100000
所以总损益为（80000-66666）-（100000-80000）=-6666
亏损6666元