How do you put cuanto cuesta la carpeta to spanish to a sendence?
It all depends on what you want "carpeta" to mean. Normally,
this means "file" or "folder", but could mean a writing desk or
table cover. "¿Cuánto cuesta la carpeta?" already is a sentence,
meaning "How much is the file?"
If you meant the English word 'carpet', that's 'alfombra' in
Spanish.
'Cuanto cuesta/vale la alfombra?' means 'How much is the
carpet?'