I have been teaching these and corrected the students.

I taught that none means zero.

The phrase in the book was:

How much did you pay?

I know the right answer is ... nothing, and not none, but I couldn't explain gramatically why.

Any ideas how I can explain this to them?
AnonymousI taught that none means zero.
It is part of this set of grammatical particles: all, some/any, none. I guess they can be called "partitives", but I'm not sure.

How much did you pay? (=quantity)
Nothing. A lot. Too much. Two hundred dollars... etc.

How much of that money is actually yours?
Some. All. None. Most of it... etc.
AnonymousI taught that none means zero.
True, but so does nothing. Emotion: smile

"What?" by itself (no noun after it) can be answered with "Nothing". It can't be answered with "None".

-- What have you read about the situation in Chicago?
-- Nothing. (Not None.)

-- What are you going to do about the dirty dishes?
-- Nothing. (Not None.)

"How much?" by itself can also be answered "Nothing", because "How much?" is often understood, in a way, as "What?" This is particularly true when money is concerned, though other situations may occur where "How much?" is like "What?".

How much did you spend? ~ What did you spend?
How much did it cost? ~ What did it cost?
How much are you willing to pay for this diamond-studded egg beater?
~ What are you willing to pay ...

So How much did you pay? (or its equivalent What did you pay?) is answered Nothing (Not None.)

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Right or wrong, this is my take. Rather than being a question of grammar, I believe it is a matter of conceptual and syntactical interpreation. Whether using "none" or "nothing" as an answer is really depending on conceptual mindsets of the people engaged in the conversation.

Nothing - is the non-existenance of something, or things. It seems to me it suggests question of "what" and "how" as in "how much did he pay for this camera ?". A: "he paid almost nothing".
Whereas, "none" - suggest context to yes and no, or amount and quantity. None - truly mean zero. Do you have any experience in sales? No, I have none.
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Thanks a lot CJ. And to the others.

All helpful and will allow me to give a reason as to why we don't use none in these circumstances.

Mr Alan