Here is a market price analysis.

Assume that a Nepalese family eats Nepalese food (Daal, Vaat, Tarkari) for US $ 5.00 a week in Nepal.
If the same size family eats the exactly same food and same quantity in USA it will cost more US $ 341.00 a week which you mentioned above.

So, you do the math and market analysis. You simply can not convert the currency. You have to do market value analysis.