Adjetivo o Adverbio？
I dont understand why POCO is regarded as adverb in following conversations?
①Cuántas chaquetas tienes?---Muy poco(why not pocas)
②Conozco a algunos jovenes cubanos,no poco(why not pocos)

Question

Answer

it is right 
1. muy pocos
2. no pocos

Answer

"Poco" may be adjective or adverb. 
As an adjective expresses "small amount" and it varies according to the name that accompanies (poco, poca, pocos, pocas) "tengo muy pocas chaquetas", "Me queda poco dinero"...
As an adverb expresses little intensity or degree, and is invariant. "Estas ropas están poco usadas".
In your phrases "poco" is an adjective and you must say "pocas chaquetas" and "pocos jóvenes".

Answer

The word "poco" is not an adjective.

There are 3 functions:
1. Determinante
2. Pronombre
3. Adverbio

I will add two links to know the explanation and some examples:

http://www.elabueloeduca.com/aprender/lengua/palabras/adverbios.html
http://roble.pntic.mec.es/msanto1/lengua/1adpreco.htm

Answer

Cuántas chaquetas tienes? - Pocas. / Muy pocas. [es correcto]