That would be by using a $1 bill, a $5 bill, and a $10 bill. Either the $1 bill or the $5 bill qualify as the "one of which is not the $10 bill". It's a matter of translating the question.
To make $16 using exactly 3 bills (with one of them not being a $10 bill), you can use one $1 bill, one $5 bill, and one $10 bill. ;
You can make $16 using exactly 3 bills by using one $1 bill, one $5 bill, and one $10 bill. This combination totals $16 while ensuring that one of the bills is not a $10 bill. The math works out as follows: $1 + $5 + $10 = $16.
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