Odds formula for "12" option

[_bester_tuff]

Hi,
its a newbie question but forgive me that, i totally forgot how to work out 12 odds from 1X2 probabilities.

lets say weve got this probabilities for 1X2 (take payout 1):

0,5 0,3 0,2

then odds for 1X is 1,25 and x2 counts to 2,0. What will the odds for 12 be (that we win either home or away side wins)and what the formula is?

[tukkk]

When 1X2 is 0,5 0,3 0,2, take X out and get 0,5 vs 0,2 ... 0,5/0,7=71,43% and 0,2/0,7=28,57%
Is that what you were looking for?

[_bester_tuff]

lol, got it now. it was the bracket wrongly put and was getting crazy numbers.

anyway thanks tukkk for reply. No, i was looking for : 1/(0,5+0,2) formula ;p