Weighing Nine Nuggets

A balance scale is level when the items weigh the same. 

Answer Put three nuggets in one tray and three nuggets in the other tray. 

Answer This puzzle definitely belongs in the category of sleight of hand. Monica, Phoebe, and Rachel actually paid only 9 each, totaling 27. The bill was 25, so subtract 25 from 27 and you have the 2 left to leave for a tip. 

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