it is right 1. muy pocos 2. no pocos

"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".

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

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