God... how many times are you all going to ask this question? you just need some LOGIC and you will find it out by yourself.
The prices on different exchanges are at times different, sometimes by 5% or even more. A couple of days ago, Polo was a lot lower than Bitfinex. How do you interpret these deviations?
every exchange has a fixed rate, it varies from all the other exchanges, the newbie exchanges are always going to have the most expensive rates for selling, and the most cheapest rates for buying.
You can make profit from this scenario if you are fast enough to deposit>withdraw>buy>sell>withdraw>sell>repeat.