请问一道数学题

anniebag

A cook went to a market to buy some eggs and paid $12. But since the eggs were quite small, he talked the seller into adding two more eggs, free of charge. As the two eggs were added, the price per dozen went down by a dollar. How many eggs did the cook bring home from the market
8
12
15
16
18  
The price of eggs was $12. Let E denote the number of eggs and P denote the price.
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请教怎么求出E的值啊？
多谢！

鸡同鸭讲

同意3楼．Ｅ＝16

garychen2009

把上面2个方程连起来。我算出来 E=16,P=3/4.

anniebag

EP=12的话，怎么求出E呢？

jessicaddq

E*P=12