What inconsistency does nick catch about where gatsby’s money came from? from where does gatsby tell nick he got his money?

The inconsistency that Nick catches about where Gatsby's money came from is that Gatsby slips up a little when he says it took him three years to earn the money for it, and when Nick questions his earlier statement that he inherited the money.  
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You are left with 8 pounds and 12 ounces or140 ounces (since there are 16 ounces per lb).divide 140 ounces by 2 ounces (serving size): you'll get 70 servings!