loool ranked i win 7 and Loss 3 Why am I bronze 5 ?

Because you were bronze last season.

i won 3, lost 7. Got silver 5. I feel bad for you. I'd love bronze 5. i'm climbing s5 like nothing atm.

I want to explain how promotions work in detail:

Unless you're a new player, the opponents you meet in promotions are the same as the last time you played ranked. Nothing changed about that. You have a hidden MMR as well as your opponents ,winning increases your MMR, loosing decreases that - however the amount of increase or decrease depends on the difference of your MMR to that of your opponents.

Your placement is not determined on flat numbers of wins and loses in promotions. They are calculated by the MMR you have reached after those 10 games. If your MMR started on a Bronze 5 level e.g. you will still be the same tier if your MMR did not increase to a bronze 4 level throughout your promos. Sometimes players have such a low MMR from the previous season, that even winning 10 games straight is not enough to increase their MMR to a bronze 4 level - remaining bronze 5.

Now many players consider that to be unfair because they feel to be just the same they were before the promos - which is not the case. After 10 games of winning their MMR will definately have increased which means they will have an easier time to climb in the division in terms of LP gains and loses because of their greatly increased MMR.

I hope this clarifies the system to you a bit more.

You can NEVER be placed higher than your ending rank previous season.

If you ended last season in B5, you can win all 10 games and you will be placed in B5 still. The rank reset at the end of season only does a soft reset on your MMR which basically means it doesn't set it to zero. It probably drops it by a percentage which after placements would place you close to the rank you ended on, but never over it and as far as I know, never places you at the same rank either. Your performance in placements determines how close you would be placed to your last season rank.