Since Google Adsense has made the requirements more stringent, you need at least 20, and they must be high quality. High quality means sufficient length and proper use of language.
From the way you phrased your question, I can see English is not your first language. If you can't write in proper English, it will be much harder to get approved. I suggest you hire an editor, translator, or proofreader to correct your grammar. You can also buy content from native speakers.
It's easier to get an Adsense account if you apply with your own site rather than HubPages. If you create your own site, be sure to write your articles in your native language.