need confirmation about ROI...newb question

Just need a quick confirmation about ROI so that I know I am caluclating right. Sorry I suck at math haha.

Say I play 5 22's and place 1st,2nd,3rd,4th,5th respectivley, for a total profit of 136.

so therefore;

total profit(136) MINUS total buyin(110) divided by total buyins (110) = 23.6% ROI

correct??

[Mr_J]

No. Your roi= profit/cost.

Your profit your return-cost.

Return is the amount you won. So +$100 (1st), +$60 (2nd), +$40 (3rd) and +$0 for both the 4th and 5th. So total return was +$200.

Your cost was 5x$22, =$110.

Profit = $200-$110 = $90

ROI = 90/110, which is 82%

[Mr_J]

The other way is just to add up just the profit (= winnings - buyin), so $78 for 1st, $38 for 2nd, $18 for 3rd, and -$22 each for 4th and 5th (=$90). Then you just do the profit divided by cost again, or 90/110.

[Exitonly]

Or, you can be an idiot like me, and calculate it as (Total winnings/Total Buyins) -1.

I'm really tired, and i don't understand how that gets me the same answer... but it does. and thats how i did it in my spreadsheet (for mtt's) and it spits out the same number.