Well, what are your websites about? What niche?
We can't tell you how long it'll take to earn $10/day from Adsense - because its not up to us, its your job.
How much are you making now? Is your content unique? How are you promoting your site?
There isn't any "get rich" answer to this - but, in order to make money online(adsense included), you need to put in the work - which means, in order to make $10/day with Adsense - your traffic numbers need to be decent, and your content decent as well.
Good luck! And remember, the more quality content that you have - and you promote it, the better you're off because you could earn possibly more.