有这样一个问题:

During a given year ,the following activities occur:

1.A silver mining company pays its workers $200,000 to mine 75 pounds of silver. The silver is then sold to a jewelry manufacturer for $300,000

2.the jewelry manufacturer pays its workers $250,000 to make silver necklaces, which it sells directly to consumers for $1000,000.

A, Using the "productiong of final goods" approch ,what is GDP in this economy?

B,how adout use "value added" approch，ＧＤＰ?

C,how about use income approch，ＧＤＰ?

第一个问题，我觉得答案是＄１０００，０００

第二个问题中，用＂ＶＡＬＵＥ　ＡＤＤＥＤ　＂算，我算出是＄６５０，０００．因为＄３００，０００－＄２００，０００＝＄１００，０００是公司的ＰＲＯＦＩＴ，　＄１０００，０００－＄３００，０００－＄２５０，０００＝＄４５０，０００．所以总的是＄５５０，０００．

第三个问题中，ＴＯＴＡＬ　ＷＡＧＥＳ　是＄４５０，０００．ＰＲＯＦＩＴ　是＄８５０，０００．所以总数ＧＤＰ是＄８５０，０００．

可是怎么会这样？我知道我肯定是算错了，怎么会有不一样的结果？

向大家请教怎么算？？？？？