Mean is the average number in a set of data. To calculate mean, you add up all the numbers in a set of data and divide that sum by the amount of numbers you just added up. Example: numbers: 2, 2, 1, 3. 2+2+1+3=8.
You wear your wedding ring on the left hand, the finger next to your pinky finger. It is usually the third finger of the left hand, but there's no rule saying that it has to be that finger. In some parts of the world people wear it on their right hands, and in other parts of the world wedding rings are not worn at all.
In traditional Jewish wedding ceremonies, the ring is placed on the index finger, but other traditions record placing it on the middle finger or the thumb, most commonly in recent times. Today, the ring usually is moved to the ring finger after the ceremony. Some Jewish grooms have adopted wearing a wedding ring.