Mills & Decimal Parts: Express 12.5 mills as a decimal part of $1.00

[KWF]

Express 12.5 mills as a decimal part of $1.00.

Is the correct answer $0.0125 or 0.0125 without the dollar sign?

Here is how I convert mills to dollars: 12.5 mills * $0.001/mill.
The answer would have a dollar sign since the mills units cancel, but the answer I have seen in the teacher's edition textbook does not use a dollar sign, just 0.0125.

 

[HallsofIvy]

A "mill" is 1/1000 of a dollar so 1/10 of a penny ("cent"). So 12.5 mills is 1.25 cents which is 0.0125 dollars.

 

[Dr.Peterson]

Express 12.5 mills as a decimal part of $1.00.

Is the correct answer $0.0125 or 0.0125 without the dollar sign?

Here is how I convert mills to dollars: 12.5 mills * $0.001/mill.
The answer would have a dollar sign since the mills units cancel, but the answer I have seen in the teacher's edition textbook does not use a dollar sign, just 0.0125.

I would call this an ambiguity of the phrasing of the question. Don't let it distract you from the fact that your math is correct!

There is nothing at all wrong in saying $0.0125, including the unit. Probably they are thinking that in asking for "a decimal part of $1.00", they have already stated the unit, and are asking only for the number.

It's as if they asked for the number of ounces in a pound, and want the answer 16, because that is the "number"; they would want you to fill in the blank, "_____ ounces", and only 16 goes in the blank. But you would be perfectly right to say that a pound is 16 ounces, including the unit for clarity.