Whereas negative (-) odds tell you what you have to bet on the favorite to winR$100, positive (+) odds tell you how much you'll win for everyR$100 you wager on the underdog. So, a team with odds of +120 would payoutR$120 for everyR$100 wager.
In addition to "1" being commonly assigned to the starting goalkeeper, it is also common for defenders to wear numbers in the lower single digits, for strikers to wear "7" or "9" or "11", and for a team's central playmaker to wear "10".