Okay Im saving for a PS VITA which is $267.42(Correct me if Im wrong) I get $20 dollars about every 2 weeks how long do you think I'll have enough by december or january?

From today (Aug 16, 2012) to:
 the end of Dec 2012 = 137 days or 19.6 weeks
 the end of Jan 2013 = 168 days or 24 weeks
So, if you get $20 for every 2 weeks, this means:
 by end of Dec 2012, you will have = 20 x 19.6 / 2 = $195.71
 by end of Jan 2013, you will have = 20 x 24 / 2 = $240.00
You will, however, save enough by Feb 2013: 20 x 196 days / 7 days a week x 0.5 = $280.00
 the end of Dec 2012 = 137 days or 19.6 weeks
 the end of Jan 2013 = 168 days or 24 weeks
So, if you get $20 for every 2 weeks, this means:
 by end of Dec 2012, you will have = 20 x 19.6 / 2 = $195.71
 by end of Jan 2013, you will have = 20 x 24 / 2 = $240.00
You will, however, save enough by Feb 2013: 20 x 196 days / 7 days a week x 0.5 = $280.00

If you make 20 bucks every two weeks it's time to get a job. There is your mathematical answer

you need to tell us how much you have already..