Concord with "how much"

[SARDORBEK]

Hello, DEAR ALAN!
I need YOUR help!

Please, pay attention to the following sentences:

1) How much were they?
2) How much is a hamburger and chips?
3) How much are these glasses?

To be frank, I don't understand and I'm confused about the use of verbs after "How much"?
I was taught the following rules:
a) How many + plural count noun
b) How much + non-count noun
Which case is given in the examples above?

Can't I say keeping correct grammar like
1) How much was they? (since "how much" + sing.verb despite "they")
2) How many are a hamburger and chips? (since a hamburger and chips ---> plural)
3) How much is these glasses? (since "how much" + sing.verb despite "these glasses")


Dear TEACHER! Could YOU please explain at length the case to me?
THANKS A LOT!

[Alan]

'How much' here has nothing to do with number: it is a fixed expression referring to price.

Furthermore, in the examples you cite, it is not a subject, but a complement. The subject is the noun phrase following the verb, which naturally is the part of the sentence that determines verbal number.

In the case of 'a hamburger and chips', on account of a linguistic phenomenon known technically as synesis, combinations of foodstuffs, when regarded as parts of a single dish rather than as separate items, are generally treated as singular (i.e. the question refers to the price of the entire dish, not of its individual components.)

I trust this makes the matter clearer for you!